Splicing type variable contour electrode, system and method for electrolytic machining of blade disc

Abstract

The invention discloses a spliced variable-contour electrode, system and method for blade disc electrolytic machining, and relates to the technical field of electrolytic machining, the spliced variable-contour electrode for blade disc electrolytic machining comprises a plurality of tube electrode assemblies, the tube electrode assemblies are hinged in sequence, each tube electrode assembly is provided with an electrolyte channel, and the electrolyte channels are communicated with the tube electrode assemblies; a liquid inlet and a liquid outlet which are communicated with the electrolyte channel are formed in each tubular electrode assembly, and in the working state, any two adjacent tubular electrode assemblies can rotate relatively so that the overall contour of the multiple tubular electrode assemblies can be matched with the section contour of a cascade channel to be machined. The machining method can meet the machining requirement of a fan disc cascade channel with a distorted complex molded surface.

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 the core component of aircraft engines, 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 such as 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, the twist is large, and the flow channel is narrow. Electrolytic machining is a process method based on the principle of anodic dissolution of metal in electrolyte to achieve material removal. Compared with traditional CNC milling, it has the characteristics of high processing efficiency, no tool loss, 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 technology is to electrochemically machine various complex surfaces by performing three-dimensional movement between a rod electrode and a workpiece according to computer numerical control instructions. Therefore, CNC electrochemical machining has the combined advantages of electrochemical machining and CNC machining. However, the existing CNC electrochemical machining process generally uses a fixed-shape electrode. In this mode, the movement trajectory of the electrode is a straight-grained developable surface, which cannot meet the processing requirements of the fan disk blade channel with a twisted and complex surface. Summary of the invention

[0004] The object of the present invention is to provide a spliced ​​variable profile electrode, system and method for electrolytic machining of blade disks to solve the problems existing in the above-mentioned prior art and meet the machining 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 electrolytic machining of blade disks, comprising: a plurality of tube electrode assemblies, the plurality of tube electrode assemblies are hinged in sequence, each of the tube electrode assemblies has an electrolyte channel, the tube electrode assemblies are provided with a liquid inlet and a liquid outlet connected to the electrolyte channel, and 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 comprises a base frame and a plurality of tube electrode units, the plurality of base frames are connected in sequence 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, each of the base frames is constructed with a plurality of accommodating portions, each of the accommodating portions is 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, the base frame in the second tube electrode assembly is in a bent structure, the base frame is made of a conductive material, and during processing, the base frame maintains electrical contact with the tube electrode unit.

[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 supporting slats.

[0011] Preferably, the liquid outlet is aligned with the gap between the two supporting 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 parts, 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 accommodating portion.

[0014] The present invention also provides a blade disc electrolytic machining system, comprising an electrolyte injection device, a power supply, a driving device and the spliced ​​variable profile electrode for blade disc electrolytic 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 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 for blade disc electrolytic machining, and the driving 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 machining is closer to the actual blade profile, achieving controllable deformation of the electrode, meeting the machining requirements of fan disk blade channels with twisted and complex surfaces, and improving machining accuracy.

[0018] The present invention is installed on the base frame through discrete tube electrode units. The tube electrode units can be installed and adjusted in modules according to the requirements of different blade disk cascade channels, which is convenient for flexible replacement, and each tube electrode unit is independently supplied with liquid, which greatly shortens the electrolyte process. Only the uniformity of the liquid output of a single tube electrode unit is required to ensure the stability of the entire tool electrode in the blade cascade channel processing.

[0019] The process method adopted by the present invention is CNC sweeping electrolytic cutting. After the processing is completed, the material head in the blade channel will be cut off from the blade disk substrate for subsequent use. At the same time, the material removal of the cutting CNC electrolytic machining is limited to a small range of the electrode structure, which reduces the total machining current and the discharge of electrolytic products, improves the environmental protection of the process, and thus realizes efficient and low-cost CNC electrolytic machining of blade disks. 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 drawings required for use in the embodiments will be briefly introduced below. 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 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 of 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 , schematic diagram of the final state of the spliced ​​variable profile electrode;

[0029] Fig. 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 be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. 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 creative work 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] Combine the following Figures 1 to 9 , describing an embodiment of the present invention.

[0034] The present invention provides a spliced ​​variable profile electrode 100 for electrolytic machining of a blade disk, which is suitable for CNC electrolytic machining, such as Figure 1 to Figure 5 As shown, it includes: a plurality of tube electrode assemblies, the plurality of 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 a working state, any two adjacent tube electrode assemblies can rotate relative to each other so that the overall contours of the plurality of tube electrode assemblies match the cross-sectional contour of the blade channel to be processed. The matching here refers to that the overall contours of the plurality of tube electrode assemblies are exactly the same or substantially the same as the cross-sectional contours of the blade channel to be processed, and the sizes are exactly the same, or the overall contours of the plurality of tube electrode assemblies are slightly smaller than the cross-sectional contour 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 during sweeping electrolytic machining of blade channels, so that the channel profile formed by electrolytic machining is closer to the actual blade profile, achieving controllable deformation of the electrode, meeting the machining requirements of fan disk blade channels with twisted and complex surfaces, and improving machining accuracy.

[0037] In addition, the present invention can realize sweeping electrolytic cutting processing. After the processing is completed, the material head 200 in the blade channel will be cut off from the blade disk substrate for subsequent use. At the same time, the material removal of the cutting CNC electrolytic processing is limited to a small range of the electrode structure, which reduces the total processing current and the discharge of electrolytic products, improves the environmental protection of the process, and thus realizes efficient and low-cost CNC electrolytic processing of blade disks.

[0038] In some embodiments, the embodiments of the present invention are 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 is a bent structure as a second tube electrode assembly, and one end of the two first tube electrode assemblies is respectively hinged to the two ends of the second tube electrode assembly.

[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 and the cross-sectional profile of the blade channel to be processed roughly the same, and 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 is not easy to accurately control.

[0040] In the related art, when CNC electrolytic machining of integral blade disks is adopted, internal spraying liquid outlet is usually adopted. The electrolyte enters from one end of the rod electrode and is sprayed from the liquid outlet of 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 length exceeding 200mm, the material removal rate is large and the electrolyte flow process 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 increase in machining speed. More seriously, the lack of local electrolyte may cause unstable machining state and even cause short circuit, damaging the electrode and 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 parts, each accommodating part 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 is a bent structure. The base frame is made of conductive material. During the processing, the base frame and the tube electrode unit 6 maintain electrical contact. It can be understood that the tube electrode unit 6 is a hollow tube structure with closed axial ends and a liquid inlet 61 and a liquid outlet 62 on its side.

[0042] This embodiment uses a base frame to fix and support multiple tube electrode units 6, realizing a discrete arrangement of the tube electrode units 6. Thus, the module installation and the discrete degree, or quantity and density of the tube electrode units 6 can be adjusted according to the requirements of different blade disk cascade channels, thereby better meeting the processing requirements, and each tube electrode unit 6 is independently supplied with liquid, which greatly shortens the electrolyte process. Only the uniformity of the liquid output of a single tube electrode unit 6 is required to ensure the stability of the entire tool electrode in the cascade channel processing.

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

[0044] Description, such as Figure 1 to Figure 4 As shown, the base frame in the first tube-electrode assembly is a first base frame 1 , and the base frame in the second tube-electrode assembly is a 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 with 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 on the tube electrode unit 6 along a straight line.

[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 slats 11, the accommodating portion is a cylindrical structure, the two support slats 11 are arranged around the accommodating portion, the inner walls of the two support slats 11 used to contact 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 slats 11. In some examples, the liquid outlet 62 is aligned with the gap 13 between the two support slats 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 supporting 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 parts, and the limiting body 12 is fixedly connected to the two supporting strips 11 . When the tube electrode unit 6 is installed in the accommodating part, 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 arranged, 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 clamped, bonded or fastened in the receiving portion.

[0054] This embodiment provides several ways of fixing 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 accommodating portion. The connection method can be snap-on, 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 electrolytic machining of blade disks 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 conducted 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 electrolytic machining of blade disks, 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 electrolytic machining of a blade disk, specifically a method for electrolytic machining of a numerically controlled blade disk, such as Figure 6 to Figure 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 electrolytic machining of the integral blade disk 300, the electrolyte injection device introduces an equal flow of electrolyte into each tube electrode unit 6, the blade disk workpiece is connected to the positive pole of the power supply, and the base frame is connected to the negative pole of the power supply. The driving device drives the base frame to drive the tube electrode unit 6 to feed downward, and at the same time drives the blade disk workpiece to move around its own axis, and realizes the blade channel processing through the three-dimensional movement of the two axes. In the process of the base frame feeding downward, the two first tube electrode assemblies are controlled to drive the hinge 2 to rotate a certain angle to realize the deformation of the overall electrode contour, so that the channel contour is better close to the actual blade profile. During the machining process, the base frame and the tube electrode unit 6 maintain electrical contact.

[0059] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A spliced ​​variable profile electrode for electrochemical machining of a blade disk, characterized in that: include: A plurality of tube electrode assemblies are hinged in sequence, each of the tube electrode assemblies has 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 contour of the plurality of tube electrode assemblies matches the cross-sectional contour of the blade channel to be processed.

2. The spliced ​​variable profile electrode for electrochemical machining of a blade disk according to claim 1, characterized in that: 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 a second tube electrode assembly in a bent structure, and one end of the two first tube electrode assemblies is hinged to the two ends of the second tube electrode assembly respectively.

3. The spliced ​​variable profile electrode for electrochemical machining of a leaf disk according to claim 2, characterized in that: Each of the tube electrode assemblies comprises a base frame and a plurality of tube electrode units, each of the tube electrode units has the electrolyte channel, the tube electrode unit is provided with the liquid inlet and the liquid outlet, the plurality of base frames are sequentially connected by hinges, each of the base frames is constructed with a plurality of accommodating parts, each of the accommodating parts is 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, the base frame in the second tube electrode assembly is in a bent structure, the base frame is made of a conductive material, and during the processing, the base frame maintains electrical contact with the tube electrode unit.

4. The spliced ​​variable profile electrode for electrochemical machining of a leaf disk according to claim 3, characterized in that: 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.

5. The spliced ​​variable profile electrode for electrochemical machining of a leaf disk according to claim 3, 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 is in contact with the inner wall of the supporting slats.

6. The spliced ​​variable profile electrode for electrochemical machining of a leaf disk according to claim 5, characterized in that: The liquid outlet is aligned with the gap between the two supporting strips.

7. The spliced ​​variable profile electrode for electrochemical machining of a leaf disk according to claim 5, characterized in that: A limiting body is arranged 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 parts, both ends of the tube electrode unit are in contact with the limiting body.

8. The spliced ​​variable profile electrode for electrochemical machining of a leaf disk according to claim 3, characterized in that: The tube electrode unit is clamped, bonded or fastened in the accommodation portion.

9. A blade disk electrochemical machining system, characterized in that: It comprises an electrolyte injection device, a power supply, a driving device and a spliced ​​variable profile electrode for electrolytic machining of a blade disk as claimed in any one of claims 1 to 8; the electrolyte injection device is connected to a liquid inlet, the anode of the power supply is used to conduct with a workpiece, the cathode of the power supply is conducted with the tube electrode assembly, the driving device is used to drive the workpiece to rotate, the driving device is used to drive a plurality of the tube electrode assemblies to rotate relative to each other to change the overall profile of the spliced ​​variable profile electrode for electrolytic machining of a blade disk, and the driving device is used to drive the tube electrode assembly to feed along the axial direction of the blade disk.

10. A method for electrochemical machining of a blade disk, characterized in that: 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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