Electric arc-mechanical composite cutting machining system and method

Abstract

The invention provides an electric arc-mechanical composite cutting machining system and method. The electric arc-mechanical composite cutting machining system comprises a water tank, a main shaft, an electric brush, a chuck, a disc saw, a graphite disc, a workbench and a controller. The rotary joint is rotatably connected to the main shaft, the main shaft is driven by the motor to rotate, the chuck is mounted at the bottom end of the main shaft, the adapter tube is mounted at the bottom end of the chuck, the rotary cutter consisting of the disc saw and the graphite disc is mounted on the adapter tube, the workbench is arranged in a space below the rotary cutter, and a workpiece is mounted in a water tank on the workbench. According to the electric arc cutting process, materials can be efficiently corroded on the premise that no remarkable contact stress exists; an electric arc-mechanical composite cutting technology is achieved through a rotary cutter, a part of base material is softened while materials are removed through electric arc large allowance, and the completeness of a cutting seam is improved by combining with auxiliary cutting of a rotary saw; inner and outer combined flushing liquid is adopted for machining, the inner flushing liquid can directly flush a machining area to enhance chip removal and cooling efficiency, the bad discharge rate is reduced, and high efficiency and practicability are achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of cutting processing, and in particular relates to an arc-mechanical composite cutting processing system and method. Background Art

[0002] In the field of aero-engines, high-temperature nickel-based alloys have become ideal materials for manufacturing hot-end components due to their excellent high-temperature performance and oxidation resistance. In particular, key components such as blades and blisks are often produced using casting processes to ensure component integrity and material properties. However, after casting, large volumes of pouring and risers will be produced, which poses a huge challenge to subsequent processing. Due to the high hardness and strength of high-temperature nickel-based alloys, traditional grinding wheel cutting will cause severe tool wear, and slag inclusions often exist on the surface of the workpiece after processing. These problems have led to a significant increase in production costs and reduced processing efficiency.

[0003] Arc machining has received extensive attention in the field of special machining due to its high material removal rate. Its energy density is much higher than that of traditional EDM, and it has no significant contact stress. It is particularly suitable for the efficient machining of high-temperature nickel-based alloys and is considered to be a potential solution for high-temperature nickel-based alloy pouring and riser cutting. However, the high temperature and rapid cooling generated during arc machining lead to the formation of more obvious defects such as recast layer, heat-affected layer and cracks on the surface of the workpiece, which significantly reduces the surface quality of the workpiece, which may also have an adverse effect on the fatigue life of the component. Therefore, how to effectively remove heat-induced surface defects such as recast layer during arc cutting and improve the surface quality of the workpiece has become a technical problem that needs to be solved urgently.

[0004] Based on this, an arc-mechanical composite cutting processing system is proposed. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide an arc-mechanical composite cutting processing system and method in view of the deficiencies of the above-mentioned prior art, so as to solve the problems raised in the above-mentioned background technology.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0007] In the first aspect, an arc-mechanical composite cutting processing system includes a water tank, a spindle, a brush, a chuck, a disk, a graphite disk, a worktable and a controller;

[0008] The water tank contains working fluid, which is delivered to the tee through a pipeline and a water pump, and the other two passages of the tee are connected to the rotary joint and the adapter respectively;

[0009] The rotary joint is rotatably connected to the main shaft, the main shaft is mounted on the insulating slide fixing plate through the first angular contact ball bearing and the second angular contact ball bearing, the insulating slide fixing plate is also mounted with a motor, the main shaft is driven to rotate by the motor, the chuck is mounted on the bottom end of the main shaft, the bottom end of the chuck is mounted with a transfer tube, and the rotary tool composed of the disc and the graphite disc is mounted on the transfer tube;

[0010] The workbench is arranged in the space below the rotating tool, and a workpiece is mounted in the water tank on the workbench through a fixture, and the workpiece is electrically connected to the positive pole of the DC power supply. A conductive ring is arranged outside the spindle, and a brush is arranged on the conductive ring, and the brush is electrically connected to the negative pole of the DC power supply.

[0011] The insulating slide fixing plate and the workbench are respectively connected to the controller by signal, and the controller is connected to the control computer by signal. The cutting operation can be completed by the control computer scheduling the controller to drive the movement of the insulating slide fixing plate and the workbench.

[0012] As a further explanation of the present invention, the disk saw is provided with three saw blades, and the graphite disk is provided with three graphite sheets. The three saw blades are fixed on the outside of the groove at equal intervals in a circular shape, and the three graphite sheets are fixed on the outside of the boss at equal intervals in a circular shape. The boss is assembled in the groove, and the saw blades and graphite sheets are staggered, and the boss and the groove are fixed to the transfer tube by screws.

[0013] As a further illustration of the present invention, the boss of the graphite disk is connected to the inner cavity of the transfer tube, and a sealing ring is provided at the connection point.

[0014] As a further illustration of the present invention, three arc-shaped through holes are arranged in the graphite sheet of the graphite disk, and the inner cavity of the transfer tube is connected with the outside through the arc-shaped through holes.

[0015] As a further illustration of the present invention, a cutting edge is arranged at the front end of the saw blade of the disk saw, and abrasive grains are arranged on the upper surface and the lower surface of the saw blade.

[0016] As a further illustration of the present invention, a first flow meter and a first valve are provided on the connecting pipeline between the water pump and the tee.

[0017] As a further illustration of the present invention, the water tank is also connected to a filter via a pipeline, and the liquid outlet of the filter is connected to the water tank via a pipeline.

[0018] As a further illustration of the present invention, a second flow meter and a second valve are provided on the connecting pipeline between the water tank and the filter.

[0019] As a further description of the present invention, a main shaft pulley is arranged on the main shaft, a driving pulley is arranged on the output shaft of the motor, and the driving pulley and the main shaft pulley are driven and connected via a belt ring.

[0020] As a further illustration of the present invention, an oscilloscope is also connected to the positive and negative circuits of the DC power supply to monitor the processing voltage, and the processing current can be synchronously detected by a current probe.

[0021] In a second aspect, a processing method of an arc-mechanical composite cutting processing system comprises the following steps:

[0022] The workpiece is mounted in the water tank on the workbench through a fixture, and the insulating slide fixing plate and the workbench are driven to move by controlling the computer scheduling controller, so that the rotary tool rotates and approaches the workpiece;

[0023] When the graphite disk rotates and faces the workpiece, arc plasma is generated under the action of DC power supply, and the high temperature generated can quickly melt the workpiece to initially form a cutting seam;

[0024] Part of the molten material re-adheres to the workpiece surface during the movement to form a recast layer. As the rotary cutter continues to rotate and feed as a whole, the saw blade of the disc saw begins to contact the workpiece, and the initially formed softened recast layer and part of the preheated matrix material are removed by cutting at the edge of the saw blade.

[0025] The rotating tool drives the disk saw and the graphite disk to rotate during the rotation process, and a recast layer is formed at the front end of the workpiece slit. Since the cross-sectional area of ​​the graphite disk is larger, a recast layer is also generated on the upper and lower surfaces of the workpiece slit. The front end of the disk saw blade is provided with a blade, and abrasive grains are provided on the upper and lower surfaces of the saw blade. When the disk saw blade enters the slit, the upper and lower surfaces of the slit are ground synchronously, and the material surface of the workpiece is continuously ground at the same time.

[0026] During the cutting process, the arc-shaped through hole can complete the connection between the inner cavity of the transfer tube and the outside world. When the internal flushing liquid flows into the inner hole of the transfer tube, the internal flushing liquid can flow into the inside of the slit along the arc-shaped through hole of the graphite sheet. When the graphite disk rotates to face the slit, the inner hole of the graphite sheet faces the front end of the processing area, cools the processing surface and flushes the electro-erosion particles. The external flushing liquid is arranged at the horizontal plane of the slit, and uses the centrifugal force of the rotating tool to enter the processing gap, and cooperates with the internal flushing liquid to flush the electro-erosion particles out of the processing area faster, thereby improving the processing stability and completing the cutting operation.

[0027] Compared with the prior art, the present invention has the following advantages:

[0028] The arc cutting process in the present invention can efficiently dissolve materials without significant contact stress; the arc-mechanical composite cutting process is realized by a rotating tool, and the arc is used to remove a large amount of material while softening part of the base material, and the integrity of the slit is improved by combining with a disk saw to assist in cutting; the abrasive particles on the upper and lower surfaces of the disk saw can be easily removed when thermally induced surface defects such as the recast layer are initially formed, thereby reducing the grinding force and improving the surface quality of the casting and recycled cutting materials; the internal and external combined flushing liquid is used for processing, the internal flushing liquid can directly flush the processing area to enhance the chip removal and cooling efficiency and reduce the bad discharge rate, and the external flushing liquid can also enter the processing area in combination with the rotating movement of the electrode to assist in chip removal and cooling, so that the processing process tends to be stable and reliable, so that the process can adapt to the complex working conditions of deep and narrow slits, and is efficient and practical. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is an overall schematic diagram of the present invention;

[0030] Figure 2 It is an exploded schematic diagram of the rotary cutter structure of the present invention;

[0031] Figure 3 is a perspective view of the graphite disk structure of the present invention;

[0032] Figure 4 is a top view of the rotary tool machining process of the present invention;

[0033] Figure 5 is a side view of the rotary tool machining process of the present invention;

[0034] Figure 6 It is a schematic diagram of the cooperative operation process of the rotary cutter and the external flushing liquid of the present invention.

[0035] Description of reference numerals:

[0036] 1-water tank; 2-working fluid; 3-water pump; 4-first flowmeter; 5-first valve; 6-tee; 7-swivel joint; 8-spindle; 9-conductive ring; 10-brush; 11-first angular contact ball bearing; 12-pulley; 13-belt; 14-pulley; 15-motor; 16-second angular contact ball bearing; 17-chuck; 18-adapter; 19-external flushing fluid; 20-adapter tube; 21-disc saw; 22-graphite disk; 23-insulating slide fixing plate; 24-fixture; 25-workpiece; 26-water tank; 27-workbench; 28-oscilloscope; 29-DC power supply; 30-second flowmeter; 31-second valve; 32-filter; 33-control computer; 34-controller; 35-sealing ring; 36-screw; 37-plasma; 38-recast layer; 39-electro-etching particles. DETAILED DESCRIPTION

[0037] 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.

[0038] like Figure 1-6 As shown, the present invention provides a technical solution: an arc-mechanical composite cutting processing system, comprising a water tank 1, a spindle 8, a brush 10, a chuck 17, a plate 21, a graphite plate 22, a workbench 27 and a controller 34;

[0039] Among them, the water tank 1 contains working fluid 2, which is sent to the tee 6 through a pipeline and a water pump 3. A first flowmeter 4 and a first valve 5 are provided on the connecting pipeline between the water pump 3 and the tee 6 to control the flow of the working fluid 2.

[0040] The other two passages of the tee 6 are connected to the rotary joint 7 and the adapter 18 respectively. A part of the working fluid 2 flows into the inner flow channel of the machine tool through the rotary joint 7 and passes through the inner hole of the spindle 8 to form the inner flushing liquid, and the other part of the working fluid 2 flows into the adapter 18 to form the outer flushing liquid 19.

[0041] The rotary joint 7 is rotatably connected to the main shaft 8, and the main shaft 8 is mounted on the insulating slide fixing plate 24 through the first angular contact ball bearing 11 and the second angular contact ball bearing 16. The insulating slide fixing plate 24 is also mounted with a motor 15, and the rotation of the main shaft 8 is driven by the motor 15. A main shaft pulley 12 is provided on the main shaft 8, and a driving pulley 14 is provided on the output shaft of the motor 15. The driving pulley 14 and the main shaft pulley 12 are driven and connected via a belt ring 13.

[0042] The chuck 17 is mounted at the bottom end of the spindle 8, a transfer tube 20 is mounted at the bottom end of the chuck 17, and a rotating tool consisting of a disk 21 and a graphite disk 22 is mounted on the transfer tube 20;

[0043] The disk saw 21 is provided with three saw blades, and the graphite disk 22 is provided with three graphite sheets. The three saw blades are fixed on the outside of the groove at equal intervals in a circular shape, and the three graphite sheets are fixed on the outside of the boss at equal intervals in a circular shape. The boss is assembled in the groove, and the saw blades and graphite sheets are staggered. The boss and the groove are fixed on the transfer tube 20 by screws 36.

[0044] The workbench 27 is arranged in the space below the rotating tool, and a workpiece 25 is installed in the water tank 26 on the workbench 27 through a clamp 24. The water tank 26 is also connected to a filter 32 through a pipeline. The liquid outlet of the filter 32 is connected to the water tank 1 through a pipeline. A second flow meter 30 and a second valve 31 are arranged on the connecting pipeline between the water tank 26 and the filter 32.

[0045] The workpiece 25 is electrically connected to the positive pole of the DC power supply 29. A conductive ring 9 is disposed outside the spindle 8. A brush 10 is disposed on the conductive ring 9. The brush 10 is electrically connected to the negative pole of the DC power supply 29.

[0046] The insulating slide fixing plate 24 and the workbench 27 are respectively connected to the controller 34 by signal, and the controller 34 is connected to the control computer 33 by signal. The control computer 33 schedules the controller 34 to drive the movement of the insulating slide fixing plate 23 and the workbench 27 to complete the cutting operation.

[0047] An oscilloscope 28 is also connected to the positive and negative circuits of the DC power supply 29 to monitor the machining voltage, and the machining current can be synchronously detected through a current probe.

[0048] The processing method of the arc-mechanical composite cutting processing system comprises the following steps:

[0049] During use, the control computer 33 dispatches the controller 34 to drive the movement of the insulating slide fixing plate 23 and the workbench 27, so that the rotating tool rotates and approaches the workpiece 25. When the graphite disk 22 rotates to face the workpiece 25, arc plasma 37 is generated under the action of the DC power supply 29. The high temperature generated can quickly melt the workpiece 25 and initially form a cutting seam. Due to the large volume of the molten material and the small gap, part of the molten material re-adheres to the surface of the workpiece 25 during movement to form a recast layer 38. As the tool continues to rotate and feed as a whole, the saw blade of the disk saw 21 begins to contact the workpiece 25, and the initially formed softened recast layer and part of the preheated matrix material are cut away by the blade end of the saw blade, thereby improving the surface integrity of the cutting seam. Although there is also a discharge gap between the disk saw 21 and the workpiece 25, the contact area between the front end of the blade and the workpiece 25 is very small, and the probability of discharge is very low and can be ignored.

[0050] The rotation of the rotating tool drives the disc saw 21 and the graphite disc 22 to rotate, and a recast layer 38 is formed at the front end of the cut of the workpiece 25. Since the graphite disc 22 has a higher cross-sectional area, a recast layer 38 is also produced on the upper and lower surfaces of the cut of the workpiece 25. A blade is provided at the front end of the saw blade of the disc saw 21, and abrasive grains are provided on the upper and lower surfaces of the saw blade for grinding during the cutting process. When the saw blade of the disc saw 21 enters the cut, the upper and lower surfaces of the cut are ground synchronously. Since the recast layer 38 is initially formed and the material is preheated and softened, there is no significant grinding force. The disc 21 not only removes the recast layer 38, but also continuously grinds the surface of the workpiece 25 material, thereby improving the processing quality of the casting surface and the recycled material surface.

[0051] Since the slit is narrow and deep during the cutting process, it is difficult to discharge the processed product in time by relying solely on the external flushing liquid 19, which may cause a short circuit and increase blade wear, while reducing processing efficiency and surface quality. The boss of the graphite disk 22 is connected to the inner cavity of the transfer tube 20, and a sealing ring 35 is provided at the connection point, and a sealing operation is performed through the sealing ring 35. Three arc-shaped through holes are provided in the graphite sheet of the graphite disk 22, and the inner cavity of the transfer tube 20 is connected to the outside world through the arc-shaped through holes. When the internal flushing liquid flows into the inner hole of the transfer tube 20, it can flow into the slit along the arc-shaped through holes of the graphite sheet.

[0052] When the graphite disk 22 rotates to face the cutting seam, the inner hole of its graphite sheet faces the front end of the processing area, cooling the processing surface and flushing the electro-erosion particles 39. The external flushing liquid 19 is arranged at the horizontal plane of the cutting seam, and uses the centrifugal force of the rotating tool's rotation to enter the narrow processing gap, and cooperates with the internal flushing liquid to flush the electro-erosion particles 39 out of the processing area faster, thereby improving the processing stability.

[0053] In addition, after the graphite disk 22 is rotated out of the cutting slit, it can continue to act on the processing area to assist in chip removal and cool the front end blade of the disk saw 21.

[0054] The arc cutting process in this embodiment can efficiently melt materials without significant contact stress; the arc-mechanical composite cutting process is realized by rotating the tool, and the arc is used to remove a large amount of material while softening part of the base material, and the disk saw 21 is combined to assist in cutting to improve the integrity of the slit; the abrasive particles on the upper and lower surfaces of the disk saw 21 can be easily removed when thermally induced surface defects such as the recast layer are initially formed, reducing the grinding force and improving the surface quality of the casting and recycled cutting materials; the internal and external combined flushing liquid is used for processing, the internal flushing liquid can directly flush the processing area to enhance chip removal and cooling efficiency, and reduce the bad discharge rate, and the external flushing liquid can also enter the processing area in combination with the rotating movement of the electrode to assist in chip removal and cooling, so that the processing process tends to be stable and reliable, so that the process can adapt to the complex working conditions of deep and narrow slits, and is efficient and practical.

[0055] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0056] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An arc-mechanical composite cutting system, characterized in that: It comprises a water tank (1), a main shaft (8), a brush (10), a chuck (17), a plate (21), a graphite plate (22), a workbench (27) and a controller (34); The water tank (1) contains a working fluid (2), and the working fluid (2) in the water tank (1) is delivered to the tee (6) through a pipeline and a water pump (3), and the other two passages of the tee (6) are respectively connected to the rotary joint (7) and the adapter (18); The rotary joint (7) is rotatably connected to the main shaft (8); the main shaft (8) is mounted on an insulating slide fixing plate (24) via a first angular contact ball bearing (11) and a second angular contact ball bearing (16); a motor (15) is also mounted on the insulating slide fixing plate (24); the motor (15) drives the main shaft (8) to rotate; the chuck (17) is mounted at the bottom end of the main shaft (8); a transfer tube (20) is mounted at the bottom end of the chuck (17); and a rotary tool consisting of a disk (21) and a graphite disk (22) is mounted on the transfer tube (20); The workbench (27) is arranged in the space below the rotating tool, and a workpiece (25) is installed in the water tank (26) on the workbench (27) through a clamp (24), and the workpiece (25) is electrically connected to the positive pole of a DC power supply (29). A conductive ring (9) is arranged outside the spindle (8), and a brush (10) is arranged on the conductive ring (9), and the brush (10) is electrically connected to the negative pole of the DC power supply (29); The insulating slide fixing plate (24) and the workbench (27) are respectively connected to a controller (34) by signal, and the controller (34) is connected to a control computer (33) by signal. The control computer (33) schedules the controller (34) to drive the movement of the insulating slide fixing plate (23) and the workbench (27) to complete the cutting operation.

2. The arc-mechanical composite cutting system according to claim 1, characterized in that: The disk saw (21) is provided with three saw blades, and the graphite disk (22) is provided with three graphite sheets. The three saw blades are fixed on the outside of the groove at equal intervals in a circular shape, and the three graphite sheets are fixed on the outside of the boss at equal intervals in a circular shape. The boss is assembled in the groove, and the saw blades and graphite sheets are arranged alternately. The boss and the groove are fixed on the transfer tube (20) by screws (36).

3. The arc-mechanical composite cutting system according to claim 2, characterized in that: The boss of the graphite disk (22) is connected to the inner cavity of the transfer tube (20), and a sealing ring (35) is provided at the connection point.

4. The arc-mechanical composite cutting system according to claim 3, characterized in that: Three arc-shaped through holes are arranged in the graphite sheet of the graphite disk (22), and the inner cavity of the transfer tube (20) is connected with the outside through the arc-shaped through holes.

5. The arc-mechanical composite cutting system according to claim 1, characterized in that: The front end of the saw blade of the disk saw (21) is provided with a cutting edge, and abrasive grains are provided on the upper surface and the lower surface of the saw blade.

6. The arc-mechanical composite cutting system according to claim 1, characterized in that: A first flow meter (4) and a first valve (5) are provided on the connecting pipeline between the water pump (3) and the tee (6).

7. The arc-mechanical composite cutting system according to claim 1, characterized in that: The water tank (26) is also connected to a filter (32) via a pipeline, and the liquid outlet of the filter (32) is connected to the water tank (1) via a pipeline. A second flow meter (30) and a second valve (31) are provided on the connecting pipeline between the water tank (26) and the filter (32).

8. The arc-mechanical composite cutting system according to claim 1, characterized in that: The main shaft (8) is provided with a main shaft pulley (12), and the output shaft of the motor (15) is provided with a driving pulley (14), and the driving pulley (14) and the main shaft pulley (12) are drivingly connected via a belt ring (13).

9. The arc-mechanical composite cutting system according to claim 1, characterized in that: An oscilloscope (28) is also connected to the positive and negative circuits of the DC power supply (29) for monitoring the machining voltage, and the machining current can be synchronously detected through a current probe.

10. A processing method of an arc-mechanical composite cutting system according to any one of claims 1 to 9, characterized in that: The following steps are involved: The workpiece (25) is mounted in a water tank (26) on a workbench (27) through a fixture (24), and a controller (34) is dispatched by a control computer (33) to drive the insulating slide fixing plate (23) and the workbench (27) to move, so that the rotary tool rotates and approaches the workpiece (25); When the graphite disk (22) rotates to face the workpiece (25), arc plasma (37) is generated under the action of the DC power supply (29), and the high temperature generated can quickly melt the workpiece (25) to initially form a cutting seam; During the movement, part of the molten material re-adheres to the surface of the workpiece (25) to form a recast layer (38). As the rotary cutter continues to rotate and feed as a whole, the saw blade of the disk saw (21) begins to contact the workpiece (25), and the initially formed softened recast layer and part of the preheated base material are removed by cutting with the blade end of the saw blade. The rotating tool drives the disk saw (21) and the graphite disk (22) to rotate during the rotation process, and forms a recast layer (38) at the front end of the cut of the workpiece (25). Since the cross-sectional area of ​​the graphite disk (25) is larger, the recast layer (38) is also generated on the upper surface and the lower surface of the cut of the workpiece (25). The front end of the saw blade of the disk saw (21) is provided with a blade, and the upper surface and the lower surface of the saw blade are provided with abrasive particles. When the saw blade of the disk saw (21) enters the cut, the upper surface and the lower surface of the cut are ground synchronously, and the material surface of the workpiece (25) is continuously ground at the same time; During the cutting process, the arc-shaped through hole can complete the connection between the inner cavity of the transfer tube (20) and the outside world. When the internal flushing liquid flows into the inner hole of the transfer tube (20), the internal flushing liquid can flow into the inside of the cutting groove along the arc-shaped through hole of the graphite sheet. When the graphite disk 22 rotates to face the cutting groove, the inner hole of the graphite sheet faces the front end of the processing area, cools the processing surface and flushes the electro-etching particles (39). The external flushing liquid (19) is arranged at the horizontal plane of the cutting groove, and uses the centrifugal force of the rotating tool to enter the processing gap, and cooperates with the internal flushing liquid to flush the electro-etching particles (39) out of the processing area faster, thereby improving the processing stability and completing the cutting operation.

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