Forming electrode, forming electrode group and manufacturing and using method

Abstract

The present invention provides a forming processing electrode, which is hoisted on an electric discharge machining machine to process an engine casing, comprising: a forming graphite electrode, which is hoisted on the electric discharge machining machine through a first fixing assembly; a first fixing assembly, which comprises a connecting block, a first electrode bracket, a second electrode bracket and a first electrode chuck, the forming graphite electrode is fixed on the second electrode bracket through the connecting block, the connecting block and the second electrode bracket are connected and fixed through a second connecting nut, the first electrode bracket and the second electrode bracket are connected and fixed through a first connecting nut, and the first electrode chuck is fixed on the first electrode bracket through a first fixing bolt. By processing the engine casing through the forming processing electrode group, the processing stability and processing efficiency can be improved, and the purpose of reducing tool consumption can be achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of electric spark forming processing, and in particular to forming processing electrodes, forming processing electrode groups, and manufacturing and using methods. Background Art

[0002] Nickel-based high-temperature alloys are widely used in engine casings. Nickel-based high-temperature alloys are difficult-to-cut materials. High-temperature alloys have high dynamic shear strength during cutting and the tool wears out quickly. The raw material of a certain type of casing is a forging with a complex surface contour and various shapes of mounting seats. Some mounting seats are up to 17mm deep and the material removal is more than 70%. The nickel-based high-temperature alloy used has the characteristics of high hardness and high viscosity. Conventional cutting is difficult to process, with low processing efficiency, fast tool consumption and high tool cost. Summary of the invention

[0003] In view of this, the embodiments of this specification provide a forming processing electrode, a forming processing electrode group, and a manufacturing and using method to improve the processing stability and processing efficiency and reduce tool consumption.

[0004] The embodiments of this specification provide the following technical solutions:

[0005] A forming processing electrode is hoisted on an electric spark machining machine to process an engine casing. The forming processing electrode comprises:

[0006] forming a graphite electrode, wherein the formed graphite electrode is hoisted on an electric spark machining machine through a first fixing assembly;

[0007] The first fixing assembly includes a connecting block, a first electrode bracket, a second electrode bracket and a first electrode chuck. The formed graphite electrode is fixed to the second electrode bracket through the connecting block. The connecting block and the second electrode bracket are connected and fixed through the second connecting nut. The first electrode bracket and the second electrode bracket are connected and fixed through the first connecting nut. The first electrode chuck is fixed to the first electrode bracket through the first fixing bolt.

[0008] Furthermore, the forming electrode also includes a second fixing assembly, the second fixing assembly includes a second electrode clamp, and the second electrode clamp is fixed to the second electrode bracket by a second fixing bolt.

[0009] Furthermore, the forming electrode group includes a plurality of forming electrodes.

[0010] A method for manufacturing a forming electrode group, using the forming electrode group, the method for manufacturing the forming electrode group comprises the following steps:

[0011] Step 1: Processing the electrode group according to the designed processing surface contour, and dividing the electrode group into a plurality of formed graphite electrodes;

[0012] Step 2, designing a processing surface of the forming and processing electrode group, and processing the forming and processing electrode group;

[0013] Step 3, fixing a plurality of formed graphite electrodes to the connecting block, and placing the plurality of formed graphite electrodes into an electrode library of an electric discharge machining machine respectively;

[0014] Step 4: Using the first electrode chuck to clamp each formed graphite electrode as a whole on the electric spark machining machine;

[0015] Step 5, determining the thickness of the large end wall of the engine casing, loading the formed graphite electrodes into the tool magazine of the machine tool according to the set replacement sequence and time setting, and a plurality of formed graphite electrodes are distributed in sequence on the electrode magazine of the electric discharge machining machine tool, and a plurality of formed graphite electrodes are arranged on each side;

[0016] Step 6: call out the first formed graphite electrode and process the corresponding contour of the engine casing surface according to the preset processing parameters;

[0017] Step 7: After the first formed graphite electrode is processed, the formed graphite electrode is placed back to the corresponding position of the electrode library of the EDM machine tool;

[0018] Step 8: Repeat steps 6 and 7 until all formed graphite electrodes are used up;

[0019] Step 9. According to the electrode loss during the processing, regularly grind the processing surface of the formed graphite electrode to remove the rough surface of the formed graphite electrode during the processing to ensure the processing accuracy.

[0020] Furthermore, step 2 includes:

[0021] Step 2.1, according to the structure of the engine casing, set the corresponding processing technology and process for each processing feature;

[0022] Step 2.2, obtaining the processing parameter information according to the machine tool information, tool information and cutting parameter information used for digital control milling of the engine casing;

[0023] Step 2.3, forming and processing the electrode group according to the processing parameter information.

[0024] Further, step six includes finding a processing position, and finding a processing position includes the following steps:

[0025] Step 6.1, use a standard ball to locate the center of the engine casing;

[0026] Step 6.2: Record the X and Y coordinates of the center of the circle and generate recorded data.

[0027] Furthermore, step six also includes electrode processing, and the electrode processing includes the following steps:

[0028] Step 6.3, call the first formed graphite electrode, and touch the surface of the part with the bottom of the formed graphite electrode;

[0029] Step 6.4, move upward 11mm to 12mm, and record the height coordinate point in the data record;

[0030] Step 6.5, retrieve the recorded data corresponding to the first formed graphite electrode, move the Z axis of the EDM machine tool to the top of the first electrode chuck, and grab the formed graphite electrode;

[0031] Step 6.6, process the corresponding contour of the engine casing profile according to the preset processing parameters.

[0032] Furthermore, step nine includes:

[0033] Step 9.1, fixing the formed graphite electrode to the electrode dressing device through the second fixing assembly;

[0034] Step 9.2: Use the electrode dressing device to remove the rough surface of the formed graphite electrode during the processing.

[0035] Furthermore, the preset processing parameters are: servo voltage is 50V to 70V; peak current is 250A to 260A; pulse width is 200us to 400us; pulse interval is 50us to 100us.

[0036] Furthermore, the preset machining allowance is 1.95 mm to 2.05 mm.

[0037] Compared with the prior art, the at least one technical solution adopted in the embodiments of this specification can achieve the following beneficial effects:

[0038] In order to solve the problem of removing a large amount of raw material by machining, a method of rough machining the engine casing using the EDM process with a forming machining electrode was invented. The material of the outer contour of the casing is removed by forming machining, and the surface layer subjected to EDM is removed by machining in the subsequent process, so that the surface of the part meets the requirements of the design drawing. While improving efficiency, it reduces tool consumption and processing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions of the embodiments of the present application, 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 application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0040] Figure 1 is a schematic diagram of an engine casing wrapped by a forming electrode group of the present invention;

[0041] Figure 2 It is a front view of the forming processing electrode of the present invention;

[0042] Figure 3 is a bottom view of the forming electrode of the present invention;

[0043] Figure 4 is a side view of the forming processing electrode of the present invention;

[0044] Figure 5 This is a schematic diagram of the engine case blank before machining;

[0045] Figure 6 This is a schematic diagram of the engine casing after processing;

[0046] Figure 7 This is a top view of the engine casing;

[0047] Figure 8 This is a cross-sectional view of the engine casing.

[0048] Explanation of the reference numerals: 1. engine casing; 2. forming and processing electrode group; 201. second connecting nut; 202. second electrode bracket; 203. first connecting nut; 204. first electrode bracket; 205. first electrode chuck; 206. second electrode chuck; 207. connecting block; 208. formed graphite electrode. DETAILED DESCRIPTION

[0049] The embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0050] The following describes the implementation methods of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific implementation methods, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, in the absence of conflict, the following embodiments and the features in the embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work belong to the scope of protection of the present application.

[0051] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on the present application, it should be understood by those skilled in the art that an aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number and aspect described herein can be used to implement the device and / or practice the method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this device and / or practice this method.

[0052] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application. The drawings only show components related to the present application rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0053] Additionally, in the following description, specific details are provided to facilitate a thorough understanding of the examples. However, it will be understood by those skilled in the art that the aspects described may be practiced without these specific details.

[0054] The technical solutions provided by various embodiments of the present application are described below in conjunction with the accompanying drawings.

[0055] The traditional method of processing the casing requires the design of a large number of processing tools and tool paths, and the processing is extremely difficult. Figure 5 The engine casing 1 blank shown is processed into Figure 6The method shown in the figure is to process the engine casing with various grooves such as annular grooves, special-shaped grooves, sunken grooves and arc grooves, various bosses such as reinforcing ribs and ring platforms, and various holes such as round holes, elliptical holes, and flower-shaped holes. The problem of removing large excess from the outer contour of the engine casing is solved, and a method for processing the inner and outer contours of the casing with a reasonable solution, simple operation, stability and reliability is provided, which is suitable for processing high-temperature alloys and other thin-walled materials that are difficult to machine, consume tools quickly, and require high precision.

[0056] like Figure 1 As shown, during processing, the electrode group 2 is formed to surround the outer periphery of the engine casing 1 .

[0057] like Figure 2 As shown, the forming electrode group 2 is composed of the following parts. A second connecting nut 201, a second electrode bracket 202, a first connecting nut 203, a first electrode bracket 204, a first electrode chuck 205, a second electrode chuck 206, a connecting block 207 and a formed graphite electrode 208. The formed graphite electrode 208 is mounted on the second electrode bracket 202 through the connecting block 207. The connecting block 207 and the second electrode bracket 202 are connected and fixed by the second connecting nut 201. The second electrode bracket 202 and the first electrode bracket 204 are connected and fixed by the first connecting nut 203. The connecting block 207 is a firm metal bracket.

[0058] When the first electrode chuck 205 is used to process the casing, the formed graphite electrode 208 is clamped in the electrode library and positioned at the processing position of the casing to be processed. The first electrode chuck 205 is fixed to the first electrode bracket 204 by a first fixing bolt.

[0059] The second electrode chuck 206 is used for positioning and clamping the formed graphite electrode 208 during processing and manufacturing, and is also used for positioning and clamping the formed graphite electrode 208 during grinding. The second electrode chuck 206 is fixed to the second electrode bracket 202 by a second fixing bolt.

[0060] The first electrode chuck 205 and the second electrode chuck 206 are both EROWA electrode chucks.

[0061] The formed graphite electrode 208 has a machined surface with concave-convex patterns, and is used for machining the engine casing 1 using the electric spark forming technology.

[0062] The design, manufacture and use of forming processing electrodes include the following steps:

[0063] Step 1: Design the electrospark forming machining electrode group 2 according to the outline of the aircraft engine, and divide the forming machining electrode group 2 into a plurality of forming graphite electrodes 208 according to the outline of the workpiece to be processed.

[0064] Step 2: According to the contour of the engine casing and the discharge gap, the concave and convex patterns of the machining surface of the formed graphite electrode 208 are designed according to the CNC machining programming method, and the electrode group 208 is machined.

[0065] Step 2.1, according to the structure of the engine casing 1, such as grooves, holes of various shapes, bosses and other features, set a corresponding processing technology for each processing feature;

[0066] Step 2.2, referring to the programming specification of the digital control milling machine tool, adding the machine tool information, tool information and cutting parameter information for digital control milling of the engine casing into the digital control programming system to obtain the processing parameter information to be obtained;

[0067] Step 2.3, programming using the processing technology and process of the engine casing 1 and the processing parameter information;

[0068] Step 2.4, automatically generate tool paths to process the electrode group 208 .

[0069] Step 3: fix several formed graphite electrodes 208 to the connecting block 207, and place several machined formed graphite electrodes 208 into the electrode library of the electric spark machining machine respectively.

[0070] Step 4: Use the first electrode chuck 205 to clamp each formed graphite electrode 208 on the Z axis of the EDM machine tool.

[0071] Step 5: Setting the replacement sequence of the formed graphite electrodes 208 on the EDM machine.

[0072] The replacement sequence of the formed graphite electrode 208 of this embodiment is carried out according to Table 1.

[0073] Tool magazine address (right tool magazine) Electrode No. 21# 01-OUT-PartNo 23# 12-OUT-PartNo 25# 11-OUT-PartNo 27# 10-OUT-PartNo 29# 09-OUT-PartNo 31# 08-OUT-PartNo Tool magazine address (left tool magazine) Electrode No. 12# 02-OUT-PartNo 10# 03-OUT-PartNo 08# 04-OUT-PartNo 06# 05-OUT-PartNo 04# 06-OUT-PartNo 02# 07-OUT-PartNo

[0074] Table 1

[0075] Step 6: Determine the thickness of the large end wall of the engine casing 1, and load the forming electrode group 2 into the tool magazine of the EDM machine according to Table 1. A plurality of forming graphite electrodes 208 are sequentially distributed on the electrode magazine outside the slot of the EDM machine, and a plurality of forming graphite electrodes 208 are arranged on each side.

[0076] Step 7: Automatically locate the processing position.

[0077] refer to Figure 7 and Figure 8 , a schematic diagram of alignment of the present embodiment. Figure 8 for Figure 7 Cross-sectional view of the AA portion. Figure 8 Here F is the inner circle and Z is the part surface.

[0078] Step 7.1, use the standard ball to align the center of the engine casing 1, install a φ5 standard ball on the moving bearing of the CNC machine tool, align the middle point of the four symmetrical points of the inner circle F of the engine casing 1, and record the X and Y coordinates of the center of the engine casing 1 in OUT_PartNo →PartNo.ofs→OFFSET 1;

[0079] Step 7.2, record the X and Y coordinates of the center of the circle into the replacement sequence table 1 of the formed graphite electrode 208.

[0080] Step 8: Call out the first formed graphite electrode 208, touch the part surface Z with the bottom of the formed graphite electrode 208, and then move the Z axis upwards to clear the Z axis. Call the 1# electrode in Table 1, such as Figure 8 As shown, the bottom of the formed graphite electrode 208 touches the surface Z of the edge part, and then the Z axis of the CNC machine tool moves upward by 11mm to 12mm, the Z axis is reset, and the Z axis coordinate point is recorded in OUT_PartNo→PartNo.ofs→OFFSET 1. The Z axis of the CNC machine tool moves to the top of the first formed graphite electrode 208 joint, and after precise positioning, the formed graphite electrode 208 is grasped, and the corresponding contour of the corresponding engine casing 1 profile is processed according to the set processing parameters.

[0081] The main processing parameters are servo voltage of 50V to 70V, peak current of 250A to 260A, pulse width of 200us to 400us, and pulse interval of 50us to 100us.

[0082] During the processing, the electrode retreats 0.2s in the normal direction for every 0.4-0.5s of processing to facilitate the discharge of the processed product, form a stable discharge channel, and ensure processing stability. According to the pre-set processing program, when the processing allowance is 1.95mm to 2.05mm, the processing of the first formed graphite electrode 208 is completed.

[0083] Step nine: After the processing of the first formed graphite electrode 208 is completed, the formed graphite electrode 208 is placed back to the corresponding position in the electrode library using the numerical control system.

[0084] Step 10: Repeat steps 7 to 9 until all the formed graphite electrodes 208 are used up.

[0085] Step 11: According to the electrode loss during the processing, the processing part of the formed graphite electrode 208 is regularly ground to ensure the accuracy of the part processing.

[0086] Step 11.1, fixing the formed graphite electrode 208 to the digital control processing equipment through a second fixing component;

[0087] Step 11.2, using digitally controlled processing equipment to remove the rough surface of the formed graphite electrode 208 during the processing.

[0088] refer to Figure 5 The overall structure of the engine casing is complex. The casing blank of the aircraft engine is a thin-walled cylindrical shape, and the outer surface of the shell has annular reinforcement ribs, annular platforms, and bosses. The inner surface has annular grooves, cylindrical ring belts, and spiral grooves. Circumferential oblique holes are distributed on the cylindrical ring belt. The shell wall is provided with radial holes, anisotropic and anisotropic grooves. The outer contour of the part needs to be processed at 360°. According to the contour of the engine casing, the contour of the part and the discharge gap, the corresponding forming processing electrode group 2 is designed. The forming processing electrode group 2 used for the outer contour processing is evenly divided into twelve forming graphite electrodes 208.

[0089] The EDM forming processing method used for the inner and outer contours of the engine casing has reasonable electrode design, convenient clamping, stable and reliable use, and can realize efficient processing of the inner and outer contours of the casing, realize automatic alignment, and there is no human intervention in the processing process, which improves the stability and efficiency of processing and saves costs. Compared with the traditional milling processing using digital control, it is suitable for processing high-temperature alloys and other materials that are difficult to machine and consume tools quickly, with high processing efficiency and low cost.

[0090] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the method embodiment described later, since it corresponds to the system, the description is relatively simple, and the relevant parts can be referred to the partial description of the system embodiment.

[0091] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A forming electrode, hoisted on an electric discharge machine tool for machining an engine casing (1), characterized in that: The forming electrode comprises: A formed graphite electrode (208), wherein the formed graphite electrode (208) is hoisted on the electric spark machining machine via a first fixing assembly; A first fixing assembly, the first fixing assembly comprising a connecting block (207), a first electrode support (204), a second electrode support (202) and a first electrode chuck (205); the formed graphite electrode (208) is fixed to the second electrode support (202) via the connecting block (207); the connecting block (207) and the second electrode support (202) are connected and fixed via a second connecting nut (201); the first electrode support (204) and the second electrode support (202) are connected and fixed via a first connecting nut (203); the first electrode chuck (205) is fixed to the first electrode support (204) via a first fixing bolt; and the first electrode chuck (205) is used to clamp the formed graphite electrode (208) in an electrode library and position it at a processing position of the engine casing (1) to be processed when processing the engine casing (1); The forming processing electrode further comprises a second fixing assembly, the second fixing assembly comprising a second electrode chuck (206), the second electrode chuck (206) being fixed to the second electrode support (202) via a second fixing bolt, the second electrode chuck (206) being used for positioning and clamping during the processing and manufacturing of the formed graphite electrode (208), and for positioning and clamping during the grinding of the formed graphite electrode (208).

2. A forming electrode group, characterized in that: The forming electrode group includes a plurality of the forming electrodes according to claim 1 .

3. A method for manufacturing and using a formed electrode assembly, characterized in that: The manufacturing and using method of the forming processing electrode group uses the forming processing electrode group according to claim 2, and the manufacturing and using method of the forming processing electrode group comprises the following steps: Step 1: Processing the forming electrode group (2) according to the designed processing surface contour, and dividing the forming electrode group (2) into a plurality of formed graphite electrodes (208); Step 2: designing the processing surface of the forming processing electrode group (2), and processing the forming processing electrode group (208); Step 3, fixing a plurality of formed graphite electrodes (208) to the connecting block (207), and placing the plurality of formed graphite electrodes (208) respectively into an electrode library of the electric discharge machining machine tool; Step 4: using the first electrode clamp (205) to clamp each formed graphite electrode (208) as a whole onto the electric spark machining machine; Step 5, determining the thickness of the large end wall of the engine casing (1), loading the formed graphite electrodes (208) into the tool magazine of the machine tool according to the set replacement sequence and time setting, and distributing a plurality of formed graphite electrodes (208) in sequence on the electrode magazine of the electric discharge machining machine tool, with a plurality of formed graphite electrodes (208) being arranged on each side; Step 6, calling out the first formed graphite electrode (208), and processing the corresponding contour of the engine casing (1) according to preset processing parameters; Step 7: After the first formed graphite electrode (208) is processed, the formed graphite electrode (208) is placed back into a corresponding position of an electrode library of the electric discharge machining machine; Step 8, repeating steps 6 to 7 until all formed graphite electrodes (208) are used; Step nine: according to the electrode loss during the processing, the processing surface of the formed graphite electrode (208) is regularly polished to remove the rough surface of the formed graphite electrode (208) produced during the processing, thereby ensuring the processing accuracy.

4. The method for manufacturing and using a forming electrode assembly according to claim 3, characterized in that: The second step comprises: Step 2.1, according to the structure of the engine casing (1), setting a corresponding processing technology and process for each processing feature; Step 2.2, obtaining the processing parameter information according to the machine tool information, tool information and cutting parameter information used for digital control milling of the engine casing (1); Step 2.3, forming and processing the electrode group (2) according to the processing parameter information.

5. The method for manufacturing and using a forming electrode assembly according to claim 3, characterized in that: The step six includes searching for a processing position, and the searching for a processing position includes the following steps: Step 6.1, using a standard ball to locate the center of the engine casing (1); Step 6.2: Record the X and Y coordinates of the center of the circle and generate recorded data.

6. The method for manufacturing and using a forming electrode assembly according to claim 5, characterized in that: The step six also includes electrode processing, and the electrode processing includes the following steps: Step 6.3, calling the first formed graphite electrode (208), and touching the surface of the part with the bottom of the formed graphite electrode (208); Step 6.4, move upwards by 11 mm to 12 mm, and record the height coordinate point into the recorded data; Step 6.5, retrieve the recorded data corresponding to the first formed graphite electrode (208), move the Z axis of the electric discharge machine tool to above the first electrode chuck (205), and grab the formed graphite electrode (208); Step 6.6, machining the corresponding contour of the engine casing (1) profile according to the preset machining parameters and the preset machining allowance.

7. The method for manufacturing and using a forming electrode assembly according to claim 3, characterized in that: The step nine comprises: Step 9.1, fixing the formed graphite electrode (208) to a digital control processing device via a second fixing component; Step 9.2: removing the rough surface of the formed graphite electrode (208) produced during the processing by the digital control processing equipment.

8. The method for manufacturing and using a forming electrode assembly according to claim 6, characterized in that: The preset processing parameters are: servo voltage is 50V to 70V; peak current is 250A to 260A; pulse width is 200us to 400us; pulse interval is 50us to 100us.

9. The method for manufacturing and using a forming electrode assembly according to claim 6, characterized in that: The preset machining allowance is 1.95 mm to 2.05 mm.

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