A processing method for the inner cavity of the rear cover of an actuator

Abstract

A processing method for the inner cavity of the rear cover of an actuator, comprising the following steps: Step 1, drilling. A U-drill is used for pre-drilling the bottom hole. Using a U-drill can quickly remove the stock allowance. Step 2, milling the inner cavity. A T-shaped milling cutter is used to machine the inner cavity of the rear cover. The T-shaped milling cutter can remove a large amount of allowance in the inner cavity. At the same time, the T-shaped milling cutter can break chips, and the broken chips in the inner cavity are discharged by using internal cooling cutting fluid. Step 3, turning the transition fillet R. A boring tool is used to turn the transition fillet R in the inner cavity. Step 4, turning the inner cavity. When turning the inner cavity, rough turning and finish turning are adopted, and the rough turning process is segmented. After each segment is processed, the corresponding turning tool withdraws, and then a T-shaped milling cutter enters the inner cavity to clean the iron chips. After the cleaning is completed, the processing continues until the part meets the requirements of the drawing design. The processing efficiency is greatly improved, and the roughness of the inner cavity of the part is significantly improved. The production bottleneck problem of the rear part of the actuator is successfully solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of aero-engine actuator machining, and particularly relates to a machining method for the inner cavity of an actuator rear cover. Background Art

[0002] The actuator assembly of a certain type of aero-engine is an assembly installed at the engine convergent-divergent nozzle position for connecting the nozzle regulating vane, and the piston rod is driven by fuel pressure to adjust the nozzle size. It is a main component for the operation of the engine tail nozzle. The shape of the actuator rear cover in the actuator assembly is complex (as Figure 1 shown), which is a major difficulty in the machining of actuator parts. Therefore, it is crucial to improve the machining efficiency and quality of the actuator rear cover.

[0003] According to past machining experience, the main machining steps for the inner cavity of the actuator rear cover are: rough turning the end face - drilling - rough turning the cavity - finish turning the cavity. Since chip evacuation is impossible, these machining processes need to be completed on an ordinary lathe. The machining dimensions can only be ensured by the operator's manipulation method, and the part quality completely depends on the operator's skill level. Due to poor chip evacuation in the inner cavity, problems such as poor surface roughness and severe surface vibration marks occur, and the machining cycle of a single part is relatively long, which has always been the main bottleneck restricting the factory's production and delivery. Summary of the Invention

[0004] The purpose of the present invention is to provide a machining method for the inner cavity of an actuator rear cover. Using this technology can ensure smooth chip evacuation in the inner cavity, ensure that it is not necessary to stop the machine to remove iron chips, enable continuous machining, improve machining efficiency, and ensure part quality.

[0005] To achieve the above purpose, the present invention adopts the following technical solutions:

[0006] A machining method for the inner cavity of an actuator rear cover includes the following steps:

[0007] Step 1, drilling

[0008] Use a U-drill for pre-drilling the bottom hole. Using a U-drill can quickly remove the stock allowance; the spindle speed is 1500 - 2000 r / min, and the machining allowance is 15 - 18 mm;

[0009] Step 2, milling the inner cavity

[0010] Use a T-slot milling cutter to machine the inner cavity of the rear cover. The T-slot milling cutter can remove a large amount of allowance in the inner cavity. At the same time, the T-slot milling cutter can break chips, and use internal coolant to discharge the broken chips in the inner cavity; the spindle speed is 300 - 500 r / min, and the machining allowance is 5 - 7 mm;

[0011] Step 3, turning the transition fillet R

[0012] Use a boring tool to machine the fillet R of the inner cavity transfer; the spindle speed is 1200 - 1500 r / min, and the machining allowance is 3 - 5 mm;

[0013] Step 4, machine the inner cavity

[0014] When machining the inner cavity, rough turning and finish turning are adopted, and the rough turning and finish turning processes are segmented. After each segment is machined, the corresponding turning tool is withdrawn, and then a T-shaped milling cutter is used to enter the inner cavity to clean the iron chips, ensuring that there are no continuously entangled iron chips in the inner cavity during machining. After cleaning, continue machining until the part meets the requirements of the drawing design; the rough machining spindle speed is 1000 - 1300 r / min, the machining allowance is 0.8 - 1.2 mm, and the tool feeds 0.5 mm and then retracts each time, and then a T-shaped milling cutter is used to clean the iron chips; the finish machining spindle speed is 1500 - 1800 r / min, and the feed rate is 0.17 mm / min. After finish machining to the size, retract the tool and then use a T-shaped milling cutter to clean the iron chips.

[0015] The specific content of step 4 is as follows: machine the inner cavity, retract the tool after rough machining the inner cavity, and withdraw the forming tool for machining the inner cavity; clean the iron chips, use a T-shaped milling cutter to break the iron chips in the inner cavity, and use the internal coolant of the T-shaped milling cutter to discharge the broken iron chips, and clean them up; then perform a rough turning cycle; then perform an iron chip cleaning cycle;

[0016] Machine the inner cavity, finish machine the inner cavity, and use a finish turning forming tool to complete the finish machining of the inner cavity; clean the iron chips, use a T-shaped milling cutter to break the iron chips in the inner cavity, and use the internal coolant of the T-shaped milling cutter to discharge the broken iron chips, and clean them up, and the machining is completed.

[0017] The machining allowance between rough turning and finish turning is 0.2 - 0.4 mm.

[0018] The cutting fluid used is emulsion.

[0019] The technical effects of the present invention are as follows:

[0020] A new processing method and technology are used to machine the actuator cylinder rear cover. By using new equipment and methods, the machining of the inner cavity of the actuator cylinder rear cover can be realized. It can realize the machining of 20 pieces continuously, and the machining time for each piece is about 10 minutes, greatly improving the machining efficiency. At the same time, the inner cavity profile of the part is finally machined once with a finish turning tool, and the inner cavity roughness is significantly improved; successfully solves the production bottleneck problem of the actuator cylinder rear cover, and improves the surface roughness of the inner cavity profile of the rear cover by 1 - 2 grades, greatly improving the machining efficiency; the machining efficiency and qualification rate of the part are significantly improved, and the qualification rate is increased from less than 60% to 100%. It provides new ideas for future machining and opens up a new machining method. Therefore, this manufacturing technology can be widely applied in the same industry field. Description of the Drawings

[0021] Figure 1 Schematic diagram of the rear cover of the actuator of the present invention Figure 1 (a) First perspective view Figure 1 (b) Second perspective view

[0022] Figure 2 Schematic diagram of machining the rear cover of the actuator by U-drill in the embodiment of the present invention

[0023] Figure 3 Schematic diagram of machining the rear cover of the actuator by T-slot cutter in the embodiment of the present invention

[0024] Figure 4 Schematic diagram of the inner cavity in the embodiment of the present invention Detailed implementation manners

[0025] The present invention will be further described in detail below with reference to the drawings and embodiments.

[0026] As Figures 1 to 4 shown, a machining method for the inner cavity of the rear cover of an actuator includes the following steps:

[0027] Step 1, drilling

[0028] Place the workpiece blank to be machined on the turntable of an inverted vertical lathe, and automatically feed the workpiece through the turntable. The spindle fixture directly grabs the workpiece blank to be machined; select a U-drill with a diameter of φ30mm, and operate the inverted vertical lathe to pre-drill a bottom hole at the large end of the workpiece to be machined. As Figure 2 shown, using a U-drill can quickly remove the stock allowance; the spindle speed is 1800r / min, and the machining allowance is 18mm;

[0029] Step 2, milling the inner cavity

[0030] Select a T-slot cutter. As Figure 3 shown, machine the inner cavity of the rear cover. The T-slot cutter can be used to remove a large amount of stock in the inner cavity. At the same time, the T-slot cutter can break chips, and the broken chips in the inner cavity are discharged by using internal coolant emulsion; the spindle speed is 350r / min, and the machining allowance is 7mm;

[0031] Step 3, turning the fillet R at the transition

[0032] Use a boring cutter to turn the fillet R at the transition; the spindle speed is 1500r / min, and the machining allowance is 5mm;

[0033] Step 4, turning the inner cavity

[0034] When turning the inner cavity, rough turning and finish turning are carried out in segments. Specifically:

[0035] Rough turn the inner cavity. The spindle speed for rough machining is 1000 r / min. Feed 0.5 mm and then retract the feed. Withdraw the profiling tool for turning the inner cavity. Clean the iron chips. Use a T-slot milling cutter to break up the iron chips in the inner cavity, and use the internal coolant of the T-slot milling cutter to discharge the broken iron chips with emulsion. Clean them up completely. Then continue to turn the inner cavity. Feed 0.5 mm and then retract the feed. Withdraw the profiling tool for turning the inner cavity. Clean the iron chips. Use a T-slot milling cutter to break up the iron chips in the inner cavity, and use the internal coolant cutting fluid of the T-slot milling cutter to discharge the broken iron chips. Clean them up completely. Leave a machining allowance of 0.2 mm after rough turning.

[0036] Finish turn the inner cavity. The spindle speed for finish machining is 1800 r / min. The feed rate is 0.17 mm / min. Use a finish turning profiling tool to complete the finish turning of the inner cavity. Clean the iron chips. Use a T-slot milling cutter to break up the iron chips in the inner cavity, and use the internal coolant of the T-slot milling cutter to discharge the broken iron chips with emulsion. Clean them up completely to complete the machining.

Claims

1. A processing method for the inner cavity of an actuator rear cover, characterized in that, it includes the following steps: Step 1, drilling Use a U drill to pre-drill the bottom hole and quickly remove the stock allowance with the U drill; Step 2, milling the inner cavity Use a T-shaped milling cutter to process the inner cavity of the rear cover, remove a large amount of allowance in the inner cavity with the T-shaped milling cutter. At the same time, the T-shaped milling cutter breaks the chips, and uses the internal coolant to discharge the broken chips in the inner cavity; Step 3, turning the transition fillet R Use a boring cutter to turn the transition fillet R in the inner cavity; Step 4, turning the inner cavity When turning the inner cavity, rough turning and finish turning are used, and the rough turning process is segmented. After each segment is processed, the corresponding turning tool withdraws, and then a T-shaped milling cutter enters the inner cavity to clean the iron chips, ensuring that there are no continuously entangled iron chips in the inner cavity during processing. After cleaning, continue processing until the part meets the requirements of the drawing design; The specific process of turning the inner cavity in Step 4 is as follows: Turn the inner cavity, retract the tool after rough turning the inner cavity, and withdraw the forming tool for turning the inner cavity; clean the iron chips, use a T-shaped milling cutter to break the iron chips in the inner cavity, and use the internal coolant of the T-shaped milling cutter to discharge the crushed iron chips, and clean them up; Then perform a rough turning cycle; then perform an iron chip cleaning cycle; Turn the inner cavity, finish turn the inner cavity, and use a finish turning forming tool to complete the finish turning of the inner cavity; Clean the iron chips, use a T-shaped milling cutter to break the iron chips in the inner cavity, and use the internal coolant of the T-shaped milling cutter to discharge the crushed iron chips, and clean them up, and the processing is completed.

2. The processing method for the inner cavity of an actuator rear cover according to claim 1, characterized in that: During drilling in Step 1, the spindle speed is 1500 - 2000 r / min, and the machining allowance is 15 - 18 mm.

3. The processing method for the inner cavity of an actuator rear cover according to claim 1, characterized in that: During milling the inner cavity in Step 2, the spindle speed is 300 - 500 r / min, and the machining allowance is 5 - 7 mm.

4. The processing method for the inner cavity of an actuator rear cover according to claim 1, characterized in that: During turning the transition fillet R in Step 3, the spindle speed is 1200 - 1500 r / min, and the machining allowance is 3 - 5 mm.

5. The processing method for the inner cavity of an actuator rear cover according to claim 1, characterized in that: During rough machining of turning the inner cavity in Step 4, the spindle speed is 1000 - 1300 r / min, the machining allowance is 0.8 - 1.2 mm, and the tool retracts after each feed of 0.5 mm; The spindle speed for finish machining is 1500 - 1800 r / min.

6. The processing method for the inner cavity of an actuator rear cover according to claim 1, characterized in that: The machining allowance between rough turning and finish turning is 0.2 - 0.4 mm.

7. The processing method for the inner cavity of an actuator rear cover according to claim 1, characterized in that: The internal coolant uses emulsion.

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