A lathe processing method for flow channel tail nozzle installation edge

Abstract

The present invention discloses a machining method for the installation edge of a flow channel tail nozzle, wherein the flow channel tail nozzle is clamped on a tensioning fixture, an adjustable auxiliary support block is used to support a hook on the outer wall of the flow channel tail nozzle, and then the parts are aligned to meet the machining requirements, a rubber block is embedded in the inner wall of the tail manifold to assist in tightening the tail manifold, a plurality of adjustable auxiliary support devices are added to the lower part of the tail manifold, a hollow rubber tube is wound near the lower part of the installation edge, a dynamic balance detection is performed on the machine tool workbench, and finally, the outer circle of the installation edge is rough-turned, the upper end face of the installation edge is rough-turned, the lower end face of the installation edge is rough-turned, the outer circle of the installation edge is fine-turned to the machining size requirements, the step outer circle of the upper end face of the installation edge is fine-turned to the machining size requirements, the two end faces of the upper end face of the installation edge are fine-turned to the size requirements, and the lower end face of the installation edge is fine-turned to the size requirements. The present invention solves the technical problems that the machining cannot meet the requirements and the clamping is difficult due to the very serious vibration of the tool during the machining process of the flow channel tail nozzle of the existing engine.

Description

Technical Field

[0001] The invention belongs to the field of mechanical processing, and specifically relates to a lathe processing method for the mounting edge of a large-scale thin-wall non-rotating double-layer structure eccentric part (flow channel tail nozzle). Background Art

[0002] According to the design requirements, a large thin-walled non-rotating flow channel tail nozzle with a mounting edge sealing surface needs to be installed at the tail of the aircraft engine so that the gas can smoothly enter the ejector tube. Therefore, the tail nozzle must be strictly sealed with the engine. If there is a leak, there will be large aerodynamic fluctuations and inaccurate measurement data. At the same time, part of the engine's gas will be re-inhaled by the engine, resulting in gas reflux, causing the engine temperature to be too high and the thrust to drop. With a long period of test, the repeated reflux of gas will cause the engine temperature to continue to rise, which will seriously affect the quality of the engine. On the other hand, during the test, the engine speed is high. If the gap between the flow channel tail nozzle and the engine assembly is large, it is easy to cause vibration, or even fall off and other safety hazards. Therefore, it is necessary to process qualified flow channel tail nozzles to ensure their processing quality and assembly accuracy with the engine.

[0003] like Figure 1 to Figure 3 As shown, the flow channel tail nozzle is a large thin-walled non-rotating double-layer eccentric part, which consists of a mounting edge connected to the engine and a special-shaped barrel ( Figure 1 The middle elliptical area C), the lap ring ( Figure 1 The middle ellipse area A), the extension section ( Figure 1 The test mount, hook and dozens of other parts are welded together. It is a large thin-walled non-rotating double-layer eccentric part (such as Figure 2 As shown, Figure 2 The special-shaped barrel part extending on the right side of the center causes the entire part to be eccentric). The outer wall and inner wall of the part are connected by two long support plates. The barrel wall thickness is only 1mm, the maximum radial width of the outer wall is 1200mm, and the axial length is 1400mm. After the runner tail nozzle is welded into an assembly, the installation edge needs to be processed. Due to the poor rigidity of the part, the center of gravity of the part is facing the tail runner. During the processing of the existing installation edge, the tool vibration is very serious, resulting in the inability to ensure the processing accuracy requirements of the part, and the engine assembly is not tightly sealed, which seriously affects the performance of the engine. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a lathe processing method for the installation edge of the runner tail nozzle to solve the technical problems that the existing engine runner tail nozzle is difficult to clamp and the runner tail nozzle is severely vibrated during the processing, resulting in damaged assembly accuracy.

[0005] The present invention adopts the following technical solutions:

[0006] A method for turning a flow channel tail nozzle installation edge includes clamping the flow channel tail nozzle and turning the flow channel tail nozzle installation edge, wherein the clamping of the flow channel tail nozzle includes the following steps:

[0007] Step 1: Clamp the tensioning fixture on the vertical lathe, align the tensioning fixture with the rotation center of the machine tool worktable, and then fix the tensioning fixture base on the worktable;

[0008] Step 2: Clamp the tail nozzle of the flow channel, remove the cover plate of the tensioning fixture by lifting, pass the center tube on the tail nozzle of the flow channel through the upper connecting plate of the tensioning fixture, support the hook on the outer wall of the tail nozzle of the flow channel with the auxiliary support block, and finally install the cover plate. Position the outer circle of the installation edge of the center tube through the positioning stop under the cover plate, and rotate the locking nut on the tensioning fixture so that the expansion block on the tensioning fixture just contacts the inner wall of the installation edge;

[0009] Step 3, align the runner tail nozzle, clamp it on the machine tool spindle with a dial indicator, check the end face runout of the installation side, if the end face runout exceeds the standard, adjust the auxiliary support block to meet the end face runout requirement of the installation side, press the hook with a pressure plate, and rotate the locking nut on the tensioning fixture to tighten the runner tail nozzle;

[0010] Step 4, embedding a rubber block in the inner wall of the tail manifold to assist in tightening the tail manifold, and setting an adjustable auxiliary support device at the lower part of the tail manifold;

[0011] Step 5, wrapping a hollow rubber tube around the outer surface of the runner tail nozzle and close to the lower part of the installation edge;

[0012] Step 6: Perform a dynamic balancing test on the machine tool workbench and install a balancing block on the machine tool workbench based on the test data.

[0013] As an option, each of the hooks is supported by an auxiliary support block.

[0014] As an option, the hollow rubber tube is wound from top to bottom. This is because the diameter of the upper part is small and the diameter of the lower part is large. When the rubber tube is wound from bottom to top, it will slide and the winding will not be firm, so the winding method from top to bottom is adopted.

[0015] Furthermore, the turning of the installation edge of the runner tail nozzle includes:

[0016] Step 1: Roughly turn the outer circle of the installation edge, leaving a diameter margin;

[0017] Step 2: Rough turn the upper end face of the installation edge, leaving a margin for the upper end face and the outer diameter of the step;

[0018] Step 3, rough turning the lower end surface of the installation side, leaving a margin on the lower end surface;

[0019] Step 4: Finish turning the outer circle of the mounting edge to the processing size requirement;

[0020] Step 5, finish turning the stepped outer circle of the upper end face of the mounting side to the processing size requirement;

[0021] Step 6, finish turning the two end faces of the mounting side to the required size;

[0022] Step 7: Finish turning the lower end surface of the mounting edge to the required size.

[0023] Furthermore, in step 1 and step 2, a D-shaped turning insert is used, and the tool cutting direction is directed toward the center of the worktable.

[0024] Furthermore, in step 4, step 5 and step 6, a D-shaped turning insert is used, and the tool cutting direction is directed toward the center of the worktable.

[0025] Furthermore, in step 3 and step 7, a spherical turning insert is used.

[0026] Furthermore, in step 1, step 2 and step 3, the turning adopts axial layering and the tool path is radial.

[0027] Furthermore, in step 4, multiple rubber blocks are embedded in the tail flow channel, and adjacent rubber blocks are tightly attached to each other through an inclined wedge structure. The combination of multiple rubber blocks can better adapt to the deformation of special-shaped cylindrical parts compared to a single rubber block, and the adjacent rubber blocks are squeezed and rubbed by the inclined wedge structure, which increases the mutual force and provides firm support. When the parts rotate during turning, the supporting rubber blocks are not easily thrown out.

[0028] Compared with the prior art, the present invention has the following characteristics:

[0029] (1) The present invention adopts a positioning and tensioning fixture to ensure the coaxiality requirements of the inner wall and outer wall mounting edges of the flow channel tail nozzle. At the same time, an adjustable auxiliary support fixture is used to support the hook and the tail manifold, thereby enhancing the rigidity of the parts and solving the clamping problem of large non-rotating double-layer structure eccentric parts.

[0030] (2) The present invention adopts axial layered processing in the turning of the mounting edge to reduce the cutting force. The cutting direction points to the center of the worktable. Most of the cutting force borne by the parts is radial cutting force. This solves the problem of serious tool vibration during turning of the mounting edge of the existing flow channel tail nozzle due to poor rigidity and inability to ensure accuracy. The present invention has wide promotion and application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a partial schematic cross-sectional view of a large thin-walled non-rotating double-layer structure eccentric part (flow channel tail nozzle) of the present invention;

[0032] Figure 2 for Figure 1's overhead view;

[0033] Figure 3 for Figure 2 Right-hand rotated partial view of ;

[0034] Figure 4 This is a schematic diagram of part clamping during turning processing of the present invention;

[0035] Figure 5 This is a schematic diagram of an adjustable auxiliary support block of the present invention;

[0036] Figure 6 This is a schematic cross-sectional view of the auxiliary support of the rubber block of the tail flow channel of the present invention;

[0037] Figure 7 This is a schematic diagram of the tool path for rough and fine turning of the outer circle of the mounting edge of the present invention;

[0038] Figure 8 This is a schematic diagram of the cutting route of the end surface on the mounting side of the vehicle of the present invention;

[0039] Fig. 9 This is a schematic diagram of the cutting route of the lower end surface of the mounting side of the car of the present invention;

[0040] Fig.10 It is a cross-sectional schematic diagram of the inner wall center tube of the present invention;

[0041] In the figure: 1. Mounting edge; 2. Mounting seat; 3. Support plate; 4. Center pipe; 5. Tail manifold; 6. Hook; 7. Expansion block; 8. Cover plate; 9. Positioning plate; 10. Adjustable support device; 11. Balance block; 12. Auxiliary support block; 13. Rubber block; 14. Mounting edge rough material; 15. Base; 16. Short pillar; 17. Lower connecting plate; 18. Long pillar; 19. Upper connecting plate; 20. Conical sleeve; 21. Locking nut; 22. Center pillar; 121. Pressure plate; 122. Adjustable support block; 123. Support seat; 124. Screw. DETAILED DESCRIPTION

[0042] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments, but it should not be understood that the scope of the subject matter described in the present invention is limited to the following embodiments. Without departing from the above-mentioned technical ideas of the present invention, various modifications, substitutions and changes made according to the common technical knowledge and customary means in the field are included in the scope of the present invention.

[0043] like Figure 1 to Figure 3As shown, for the runner tail nozzle, a large thin-walled non-rotating double-layer eccentric part, the processing plan for the runner tail nozzle installation edge is as follows: the runner tail nozzle is clamped on the tensioning fixture, four adjustable auxiliary support blocks 12 are used to support the hooks 6 on the outer wall of the runner tail nozzle respectively, and then the parts are aligned to meet the processing requirements, and a rubber block 13 is embedded in the inner wall of the tail manifold 5 to assist in tightening the tail manifold 5, 4 to 5 adjustable auxiliary support devices 10 (i.e., devices with adjustable support height, such as a jack) are added to the lower part of the tail manifold 5, a hollow rubber tube is wound near the lower part of the installation edge 1, the machine tool worktable is dynamically balanced and the balance block 11 is installed according to the test data, and finally the installation edge 1 of the runner tail nozzle is processed.

[0044] by Figure 1 to Figure 3 Taking the runner tail nozzle shown in as an example, the machining method of the mounting edge 1 includes:

[0045] 1. Steps for clamping the runner tail nozzle:

[0046] (1) Clamp the tensioning fixture on the vertical lathe, align the tensioning fixture with the rotation center of the machine tool worktable, and fix the tensioning fixture base on the worktable;

[0047] (2) Clamp the tail nozzle of the flow channel, remove the cover plate 8 on the tensioning fixture by lifting, pass the center tube 4 on the tail nozzle of the flow channel through the upper connecting plate 19 of the tensioning fixture, use four adjustable auxiliary support blocks 12 to support the four hooks 6 on the outer wall of the tail nozzle of the flow channel respectively, and finally install the cover plate 8 of the tensioning fixture. A positioning plate 9 is provided under the cover plate 8 to locate the outer circle of the installation edge of the center tube 4 of the tail nozzle of the flow channel. Rotate the locking nut 21 on the fixture to apply a little tension to the part, so that the expansion block 7 on the tensioning fixture just contacts the inner wall of the installation edge 1 of the part; Figure 4 The tensioning fixture is mainly composed of a tensioning block 7, a cover plate 8, a positioning plate 9, a base 15, a short support 16, a lower connecting plate 17, a long support 18, an upper connecting plate 19, a tapered sleeve 20, a locking nut 21 and a center support 22. The function of the base 15 is to support the entire fixture and is used to be fixed on the machine tool workbench. The short pillar 16 is connected to the base 15 and the lower connecting plate 17 to enhance the rigidity of the fixture (if there is only a long pillar 18, the rigidity of the fixture is poor); the long pillar 18 is connected to the lower connecting plate 17 and the upper connecting plate 19. One end of the central pillar 22 is fixed to the base 15, and the other end is provided with a thread and a cylindrical surface and passes through the upper connecting plate 19, the cover plate 8 and the tapered sleeve 20. The central pillar 22 is interference fit with the upper connecting plate 19, and the locking nut 21 is threadedly connected to the central pillar 22. By adjusting the locking nut 21, the tapered sleeve 20 is moved axially along the central pillar 22, so that the expansion block 7 slides radially, thereby tightening the fixture. The positioning plate 9 is connected to the cover plate 8. The positioning plate 9 (i.e., the positioning stop) is used to fix the outer cylindrical surface of the central tube 4 (such as Fig.10The inner surface of the center tube 4 has a circle of mounting edge, and the outer surface is in close contact with the positioning plate 9). When tightening the inner surface of the mounting edge 1, it is ensured to be concentric with the center tube 4, that is, the coaxiality requirements of the mounting edge of the inner wall and the outer wall of the flow channel tail nozzle are ensured;

[0048] (3) Align the parts, clamp them on the machine tool spindle with a dial indicator, check the end face runout of the mounting edge 1, if the end face runout exceeds 0.3 mm, adjust the four auxiliary support blocks 12 to meet the end face runout requirements, press the hook 6 with the pressure plate 121, and rotate the locking nut 21 on the fixture to tighten the parts; Figure 5 As shown, an adjustable auxiliary support block 12 includes a pressing plate 121, an adjustable support block 122, a support seat 123 and screws 124. A surface of the support seat 123 is provided with staggered horizontal T-slots and vertical T-slots. The adjustable support block 122 is connected to the T-slots by screws 124 to achieve position adjustment and fixation, and the pressing plate 121 is pressed against the upper end of the adjustable support block 122 by screws 124.

[0049] (4) If Figure 6 , three rubber blocks 13 are embedded in the inner wall of the tail manifold 5 to assist in tightening the tail manifold, and 4 to 5 adjustable auxiliary support blocks 12 are added to the lower part of the tail manifold;

[0050] (5) Wrap a hollow rubber tube near the lower part of the installation edge 1. The outer diameter of the rubber tube is Φ15-Φ20 mm, the thickness is 4-5 mm, the number of windings is 15-20, and the winding order is from top to bottom;

[0051] (6) Perform a dynamic balancing test on the machine tool workbench and install a balancing block 11 on the workbench based on the test data.

[0052] 2. The processing steps of the runner tail nozzle installation edge 1 include:

[0053] (1) Rough turn the outer circle of the mounting edge 1, such as Figure 7 , use D-type R0.8 carbide turning inserts, adopt axial layering, the tool cutting direction points to the center of the worktable, each cut depth is 0.5mm, the diameter is left with a 0.5mm margin, and the spindle speed is 8~10R / MIN;

[0054] (2) Rough turn the upper end surface of the mounting edge 1, such as Figure 8 , use D-type R0.8 carbide turning inserts, the tool cutting direction points to the center of the worktable, each cut depth is 0.5mm, 0.3mm margin is left on the end face, 0.5mm margin is left on the outer diameter of the step, and the spindle speed is 8~10R / MIN;

[0055] (3) Rough turn the lower end surface of the mounting edge 1, such as Fig. 9, use R1.5 spherical carbide turning inserts, cut 0.5mm deep per cut, leave 0.3mm margin on the end face, spindle speed 8~10R / MIN;

[0056] (4) Finish turning the outer circle of the mounting edge 1 to the machining size requirements, such as Figure 7 , use D-type R0.8 carbide turning inserts, the tool cutting direction points to the center of the worktable, and the spindle speed is 8~10R / MIN;

[0057] (5) Finish turning the outer circle of the step on the upper end face of the mounting edge 1 to the required size (such as Figure 7 The elliptical area D) is as follows Figure 7 , use D-type R0.4 carbide turning inserts, the tool cutting direction points to the center of the worktable, and the spindle speed is 8~10R / MIN;

[0058] (6) Finish the two end faces of the upper end face of the mounting edge 1 to the required size, such as Figure 8 , use D-type R0.4 carbide turning inserts, the tool cutting direction points to the center of the worktable, and the spindle speed is 8~10R / MIN;

[0059] (7) Finish turning the lower end surface of the mounting edge 1 to the required size, such as Fig. 9 , use R1.5 spherical carbide turning inserts, spindle speed 8~10R / MIN.

[0060] The contents not described in detail in the specification of the present invention belong to the prior art known to the professional and technical personnel in the field. Although the illustrative specific embodiments of the present invention are described above to facilitate the understanding of the present invention by the technical personnel in the field, it should be clear that the present invention is not limited to the scope of the specific embodiments. For ordinary technicians in the field of this technology, as long as various changes are within the spirit and scope of the present invention defined and determined by the attached claims, these changes are obvious, and all inventions and creations using the concept of the present invention are protected.

Claims

1. A lathe processing method for the installation edge of a flow channel tail nozzle, characterized in that: The method comprises the clamping of the runner tail nozzle and the turning of the installation edge of the runner tail nozzle, wherein the clamping of the runner tail nozzle comprises the following steps: Step 1: Clamp the tensioning fixture on the vertical lathe, align the tensioning fixture with the rotation center of the machine tool worktable, and then fix the tensioning fixture base on the worktable; Step 2, clamp the flow channel tail nozzle, lift and remove the cover plate (8) of the tensioning fixture, pass the center tube (4) on the flow channel tail nozzle through the upper connecting plate (19) of the tensioning fixture, support the hook (6) on the outer wall of the flow channel tail nozzle with the auxiliary support block (12), and finally install the cover plate (8), locate the outer circle of the installation edge of the center tube (4) below the cover plate (8) through the positioning stop, and rotate the locking nut (21) on the tensioning fixture so that the expansion block (7) on the tensioning fixture just contacts the inner wall of the installation edge (1); Step 3, align the runner tail nozzle, clamp it on the machine tool spindle with a dial indicator, check the end face runout of the installation edge (1), if the end face runout exceeds the standard, adjust the auxiliary support block (12) to meet the end face runout requirement of the installation edge (1), press the hook (6) with the pressure plate (121), and rotate the locking nut (21) on the tensioning fixture to tighten the runner tail nozzle; Step 4, using a rubber block embedded in the inner wall of the tail manifold (5) to assist in tightening the tail manifold (5), and providing an adjustable auxiliary support device (10) at the bottom of the tail manifold (5); Step 5, wrapping a hollow rubber tube around the outer surface of the runner tail nozzle and close to the lower part of the mounting edge (1); Step 6, perform a dynamic balancing test on the machine tool workbench, and install a balancing block (11) on the machine tool workbench according to the test data.

2. A method for machining the installation edge of a flow channel tail nozzle according to claim 1, characterized in that: Each of the hooks (6) is supported by an auxiliary support block (12).

3. The method for machining the installation edge of a flow channel tail nozzle according to claim 1, characterized in that: The hollow rubber tube is wound from top to bottom.

4. The method for machining the installation edge of a flow channel tail nozzle according to claim 1, characterized in that: The turning of the installation edge of the runner tail nozzle includes: Step 1, rough turning the outer circle of the mounting edge (1), leaving a diameter margin; Step 2, rough turning the upper end surface of the mounting edge (1), leaving an allowance for the upper end surface and the outer diameter of the step; Step 3, rough turning the lower end surface of the mounting edge (1), leaving a margin on the lower end surface; Step 4, finishing the outer circle of the mounting edge (1) to the required processing size; Step 5, finishing the stepped outer circle of the upper end surface of the mounting edge (1) to the machining size requirement; Step 6, finishing the two end surfaces of the upper end surface of the mounting edge (1) to the required size; Step 7: Finish-turn the lower end surface of the mounting edge (1) to the required size.

5. A lathe processing method for the installation edge of a flow channel tail nozzle according to claim 4, characterized in that: In step 1 and step 2, a D-type turning insert is used, and the tool cutting direction is directed toward the center of the worktable.

6. A lathe processing method for the installation edge of a flow channel tail nozzle according to claim 4, characterized in that: In the steps 4, 5 and 6, a D-shaped turning insert is used, and the tool cutting direction is directed toward the center of the worktable.

7. The method for machining the installation edge of a flow channel tail nozzle according to claim 4, characterized in that: In step 3 and step 7, a spherical turning insert is used.

8. The method for machining the installation edge of a flow channel tail nozzle according to claim 4, characterized in that: In step 1, step 2 and step 3, the turning adopts axial layering and the tool path is radial.

9. The method for machining the installation edge of a flow channel tail nozzle according to claim 1, characterized in that: In step 4, a plurality of rubber blocks are embedded in the tail flow channel (5), and adjacent rubber blocks are tightly attached to each other via an inclined wedge structure.

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