Automatic numerical control machining process method for turbine disc part of aero-engine

Abstract

The invention relates to an automatic numerical control machining process method for aero-engine turbine disc parts, which comprises the steps of formulating a turbine disc process, completing machine tool and software configuration, completing machine tool and software function development, completing cutter handle selection, completing clamp optimization, completing numerical control program simulation optimization, completing effect inspection and completing field verification. Cutting tool operation instruction compiling is completed, automatic cutting tool management is completed, batch production application is completed, and process curing is completed. According to the method, a machining tool and technological parameters are optimized and solidified, a program control method is adopted, human intervention in the numerical control machining process is reduced, a traditional numerical control machining method of manual measurement and manual tool feeding is changed, an automatic numerical control machining mode is formed, and efficient, precise and automatic numerical control machining of key procedures of typical turbine disc parts is achieved.

Description

Technical Field

[0001] The invention relates to the field of aerospace manufacturing technology, and in particular to an automated numerical control machining process for a turbine disk part of an aerospace engine. Background Art

[0002] Turbine disk parts are rotating parts and are core components of aircraft engines. Their manufacturing quality directly affects the service performance and life of the core rotor components of the engine. Due to the structural and material characteristics, the turbine disk processing technology has difficulties in cutting high-temperature alloy materials, controlling deformation of thin-walled parts, and processing mortise and tenon grooves. It also puts forward sophisticated and complex requirements for the parameter selection of cutting tools and machine tools. Due to differences in the technical level of personnel, traditional processing methods are difficult to ensure the consistency of part processing, and are accompanied by problems such as poor surface quality and low processing efficiency.

[0003] Usually, the improvement of turbine disk processing technology adopts automated CNC processing. This method is a comprehensive application of advanced technologies such as high-efficiency CNC processing, processing stability control, and processing technical index guarantee. Its main advantage is that it reduces human quality risks in batch production, improves product quality stability, reduces production costs, shortens production cycles, ensures production balance, and has significant economic benefits.

[0004] In the existing technology, the paper "Research on Machining and Deformation Control Technology of New Structure Turbine Disks" optimizes the workpiece processing route and CNC processing process plan, optimizes the tool material and tool structure, analyzes and explores the deformation law of thin-walled turbine disk processing, and ensures the processing quality of the workpiece. Wanneng analyzed the compensation processing method of rounding by in-machine measurement technology, effectively improving the processing quality of difficult-to-process parts of aircraft engines. The paper "Research and Improvement of Processing Technology of Turbine Disks of Aircraft Engines" uses unmanned CNC programming instead of manual tool compensation, solidifies the three elements of turning processing, and improves the consistency and efficiency of part processing.

[0005] Due to the complex process, high precision requirements, high processing difficulty and relatively discrete processes of aircraft engine products, the design of automated CNC machining process is difficult and the debugging cycle is long. Currently, only the automation of CNC machining processes is realized, and the automation of the entire manufacturing process has not yet been formed. The present invention will carry out research on automated machining technology, form an automated CNC machining process method route for multiple processes, and realize efficient, precise and automated CNC machining of key processes of typical turbine disk parts. Summary of the invention

[0006] In order to solve the above technical problems, the present invention provides an automated numerical control machining process for aircraft engine turbine disk parts; the specific technical solution is as follows:

[0007] An automated numerical control machining process for an aircraft engine turbine disk part comprises the following steps:

[0008] Step 1: Formulate the turbine disc process; conventional turbine disc processes include rough turning, semi-finishing turning, finishing turning, and finishing milling;

[0009] Step 2: Complete the machine tool and software configuration, and determine the automated processing unit based on the principle of one-time positioning and clamping for processing multiple parts, mainly four-axis and five-axis machining centers and CNC vertical lathes; use computer-aided processing software for multi-axis CNC processing programming;

[0010] Step 3: Complete the development of machine tools and software functions, mainly based on the requirements of automated CNC machining process to achieve high-quality and efficient machining;

[0011] Step 4: Complete the tool holder selection and select the tool holder that is suitable for the part structure and material characteristics, based on the control principles of good quality, high efficiency and low cost;

[0012] Step 5: Complete the optimization of the fixture, including structural and functional optimization. Based on the principle of optimal positioning accuracy and high clamping efficiency, the fixture adopts hydraulic clamping control to effectively control the positioning accuracy and improve the clamping efficiency.

[0013] Step 6: Complete the NC program simulation optimization and use simulation technology to verify the NC process and optimization;

[0014] Step 7: Complete the effect inspection. If the process meets the expected requirements and no better improvement direction can be found, proceed to step 8. Continue simulation optimization and proceed to step 6.

[0015] Step 8: Complete the on-site verification. If the process requirements are met, proceed to step 9. If the process requirements are not met, proceed to step 1.

[0016] Step nine, complete the preparation of tool operation instructions, formulate a tool use balance plan and tool use rules for the processing program based on tool life statistics, including the actual cutting time of the tool used on site;

[0017] Step 10: Complete automated tool management, including tool type and consumption management, machine tool tool data management, and tool life management;

[0018] Step 11: Complete the batch production application to meet the model batch production requirements;

[0019] Step 12: Complete the process solidification, form a typical feature processing template, and promote it to the same type of parts.

[0020] The described method for automated CNC machining of aircraft engine turbine disk parts has a preferred solution: in step three, the development of machine tools and software functions supports the realization of automated CNC process, mainly including the development of part coordinate detection function to prevent machining coordinate system call errors; the development of spindle cutting power adaptive control function to prevent tool breakage; the development of multiple high-level instructions to form a composite function for complex logical judgment in the machining process; the development of function integration application to realize the control of the machining process; the development of external program call function to achieve minimum memory usage; and the development of on-machine measurement function application for online measurement of machining centers and vertical lathes.

[0021] The described method for automated CNC machining of aircraft engine turbine disk parts has a preferred solution as follows: in step six, CNC program simulation optimization is completed. First, the simulation machining environment is unified, including tools, machine tool structure tree, three-dimensional model and post-processing and machine tool control system configuration; the tool change position of the part and automatic tool compensation are set to perform automatic tool change machining, which reduces the risk of manual tool change errors and improves machining efficiency; the part detection position is set, and an infrared probe and control system measurement cycle program are used to formulate features such as diameter and bevel points for online measurement; a measurement program is compiled to realize automatic measurement of the machining process, monitor the machining quality of the parts, and improve machining efficiency; cutting force and machining deformation prediction, surface roughness prediction are completed, and the CNC program is optimized.

[0022] The described method for automated CNC machining of aircraft engine turbine disk parts has a preferred embodiment in which, in step twelve, the process is solidified, including CNC machining process solidification and machine tool and clamping solidification; the machining template is to extract typical machining features in the process and generalize them to the same type of parts.

[0023] Compared with the prior art, the present invention has the following beneficial technical effects:

[0024] According to the invention, the automated CNC machining process method route for aircraft engine turbine disk parts is designed. During the implementation and promotion process, the CNC equipment machining efficiency is improved by more than 25%, and the quality of multiple parts after machining is good. The implementation of the automated CNC machining process method for turbine disk parts can effectively reduce the labor intensity of operators and improve the processing quality of products. The potential economic value created is huge and difficult to measure with numerical values.

[0025] 1) Solve the problem of low automation of parts for various products, start with one button, realize automated CNC machining of turbine disc parts, and provide technical support for future intelligent production lines.

[0026] 2) Improve the stability of the CNC machining process, avoid problems such as interruption of the CNC machining process due to human operation, lowering the machine tool magnification, adjusting the CNC program and tool changing process, etc., the cutting efficiency is improved by more than 25%, and the qualified rate reaches 90%. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a flow chart of the patented automated CNC machining process for aircraft engine turbine disc parts;

[0028] Figure 2 The chips are cut with better chip breaking effect of the tool;

[0029] Figure 3 Chips with poor chip breaking effect of the tool;

[0030] Figure 4 This is a schematic diagram of the fixture clamping configuration when processing the first side of a part in this patent;

[0031] Figure 5 This is a schematic diagram of the clamping configuration when processing the second side of a part according to the present patent;

[0032] Figure 6 This is a schematic diagram of the positioning special-shaped pin assembly in the fixture of the present patent;

[0033] Figure 7 for Figure 6 Schematic diagram of CC structure.

[0034] In the figure: 1-pressure plate, 2-parts, 3-base plate, 4-special-shaped pins, 5-elastic retaining rings, 6-M6 screws. DETAILED DESCRIPTION

[0035] The following is combined with Figure 1-7 The present invention is described in detail, but the protection scope of the present invention is not limited by the accompanying drawings.

[0036] Taking turbine disk parts as an example, an automated CNC machining process method for aircraft engine turbine disk parts is described, which includes the following steps:

[0037] Step 1: Develop a process plan for automated CNC machining of turbine discs;

[0038] 1) The program should limit the operator's authority to change processing parameters at will to the greatest extent possible, and the program execution should be stable and the program execution time standard should be consistent;

[0039] 2) Reduce and standardize the operator's actions in controlling machine tools to reduce the waste of repeated actions and the resulting human error probability;

[0040] 3) The cutting tools currently used in mass production are used as the initial research tools. All cutting speeds are given by the constant surface speed method. On the basis of the steady improvement of quality and efficiency, the chip breaking problem is further studied;

[0041] 4) When programming, focus on how to improve tool life under higher cutting speed conditions to prevent premature tool failure and program interruption;

[0042] 5) In order to avoid interference of the system's automatic tool radius compensation in certain situations, the tool center programming method is always used during programming; the automatic radius compensation function provided by the system is not used;

[0043] Step 2: Complete the machine tool and software and hardware configuration

[0044] The equipment KVl1000 Taiwan oil machine used in this technical solution is equipped with a tool probe and a workpiece measurement system. Since the equipment manufacturer's automation application technology for these two hardware items is lagging behind that of imported equipment manufacturers, by supplementing and improving the existing drivers of these two hardware items, it is possible to add developed instructions to the processing program to realize online automatic tool calibration, automatic correction of tool deviation, automatic measurement of process dimensions according to parameters, and automatic correction of specified tool wear to complete automatic compensation;

[0045] Step 3: Complete the development of machine tools and software functions

[0046] 1) Secondary development of CNC vertical lathe automatic measurement system application

[0047] %_N_AMP_OD_SPF

[0048] ;$PATH= / _N_CUS_DIR

[0049] PROC AMP_OD(REAL O_DIA, REAL AL_TOL, REAL Z_USTP, REAL Z_DMEP)DISPLOF

[0050] ;Author&Company: Kevin, Shi Liming Co.Ltd.Shenyang

[0051] ;Private data: 2012.12.28

[0052] ;---------------------------------

[0053] ;Description:

[0054] ;1.Workpiece measurement PCB for KVL-1000ATC VTL Lathe which pro-

[0055] ;ducted by YOUJI company Kunshan factory.

[0056] ;2.It needs Sinumerik 802D systems and Renishaw measurement source

[0057] ;program support,can NOT be simple reference to other machines.

[0058] ;3.Foreign body contamination analysis had been definded

[0059] 2) Secondary development of automatic tool setting program for CNC vertical lathe

[0060] %_N_AMTL_SPF

[0061] ;$PATH= / _N_CUS_DIR

[0062] PROC AMTL DISPLOF

[0063] ;Author : Kevin,Shi

[0064] ; Prepared: 2012.12.28

[0065] ;---------------------------------

[0066] ;Description:

[0067] ;1.Tool Form Measurement PCB for KVL-100ATC VTL Lathe.

[0068] ;2.It needs Sinumerik 802D systems and Marposs measurement source

[0069] ;program support,can NOT be simple reference to other machines.

[0070] Automatic tool setting application examples:

[0071]

[0072] Step 4: Complete the selection of automated CNC tools and tool holders

[0073] The cutting speed of the inserts has been steadily improved by using the constant surface speed turning method. The most significant improvement is the improvement of the cutting speed of the ceramic inserts in semi-finishing high-temperature alloys. This proves that the cutting of the tool is more stable under the constant surface speed turning method, and the surface roughness of some parts is reduced by one level.

[0074] In terms of chip breaking effect, after speeding up and adjusting and optimizing cutting depth and feed parameters, the chip breaking effect of a certain company's GIPY series inserts was better, and the chips curled more in the second deformation zone. The design of the chip breaking boss was more suitable for cutting and breaking chips of high-temperature alloys and titanium alloys. However, the chip breaking effect of the inserts of the other two companies did not change significantly after the cutting parameters were optimized. The chips remained long and straight, and were very likely to be entangled with the tool bar, thereby blocking the coolant, and workers needed to use iron hooks to hook them out regularly according to the situation.

[0075] Step 5: Optimize the automated positioning fixture

[0076] In order to ensure stable clamping and accurate positioning, hydraulic limit and force limit clamping positioning design is adopted to achieve the purpose of lifting repeated positioning, such as Figure 4 and Figure 5 As shown;

[0077] Install in the φ380 distribution circle diameter special-shaped pin positioning hole as follows Figure 6The positioning special-shaped pin assembly shown in the figure comprises a special-shaped pin 4, a circlip 5 and an M6 screw 6; the arc positioning surface of the special-shaped pin 4 with R = (φA-φ380) / 2 is facing outward, the M6 ​​screw 6 on the positioning special-shaped pin assembly is screwed in until the special-shaped pin 4 presses the surface of the base plate 3, the part 2 is installed, the part 2 is positioned and aligned with the φA inner hole and pressed, and the first surface of the part 2 is processed; after processing, the pressure plate 1 is loosened to remove the part 2, and the positioning special-shaped pin is The M6 ​​screw 6 on the assembly is unscrewed, and the special-shaped pin 4 will be taken out together with the screw due to the action of the elastic retaining ring 5; at this time, the M6 ​​screw 6 does not need to be completely unscrewed. When the special-shaped pin 4 can rotate, the arc positioning surface of R = (φB-φ380) / 2 on the special-shaped pin 4 faces outward, and the M6 ​​screw 6 is re-screwed until the special-shaped pin 4 presses the surface of the base plate 3, and the part 2 is installed. The part 2 is positioned and aligned with the φB inner hole processed on the first side and pressed, and the second side of the part 2 is started to be processed;

[0078] Step 6: Optimize NC program and simulation verification

[0079] Optimize cutting parameters through simulation technology, including cutting depth, step length, and feed speed. Optimize the tool entry and exit positions, tool change positions, and online measurement positions to achieve quality control of the machining process; change the machining plan, optimize the tool path, merge tool paths, shorten the idle stroke, and other solutions to optimize the execution program required for turning; solidify the machining parameters in the execution program through a single-segment program with multiple feeds;

[0080] Before processing, the optimized program is subjected to CNC simulation, and cutting parameter analysis is performed for each section of the tool path process to ensure the correctness of the program; through simulation analysis of processing force, deformation prediction and surface roughness prediction during processing, the matching of cutting parameters and removal amount during processing is optimized to control the deformation of parts;

[0081] Step 7: Complete the on-site inspection and verification of the effect

[0082] Through the effective process, on-site processing verification and debugging are carried out; the on-board infrared probe and control system measurement cycle of the machining center are used to complete the online measurement program compilation of diameter and bevel points, realize automatic measurement and automatic tool compensation during the machining process, reduce the risk of manual tool compensation, ensure the quality of part processing, and improve processing efficiency;

[0083] Using the combination of M05 spindle stop and M00 program pause command to pause the program is the most basic means to realize the human-computer interaction technology such as online compensation in this technical research. The typical approach is to design and process a process dimension when there is a margin for a certain diameter feature and an axial dimension feature in the front-end program, and use the combination of M05 and M00 commands to design a "planned stop". The operator completes the processing decision actions such as measurement, calculation of compensation, and input of compensation value according to the highlighted content in the operation monitoring window, and presses the start button, and the machine tool continues the subsequent processing; the following is an example of the program;

[0084] N0580 X402 F300 M09

[0085] N0585 Z15

[0086] N0590 G01 X500 Z130

[0087] N0595 M05

[0088] N0600 M00(CUE 3, MEASURE BORE 411.63MM AND ADJUST X OFFSET IN T1212,

[0089] WEAR = "VALUE-0.4") prompts the operator to measure the designed inner hole process size and input the measured deviation into the specified tool wear compensation position. The wear value is the difference between the measured value and the process design allowance of 0.4mm. In any system environment, this item can be highlighted in the program running monitoring window to serve as a prompt.

[0090] N0605 T1212 Calculate and insert the tool length compensation after the wear change in the current line;

[0091] N0610 M38

[0092] N0615 G95 G90 G71 G96 S70 M04

[0093] …

[0094] N0665 Z52.38 F1

[0095] N0670 M05

[0096] N0675 M00 (CUE 5, CHECK GAP WITH A 50MM PITTER AND ADJUST Z OFFSET INT1212 IF NECESSARY) Plan to stop again to prompt the operator to measure the designed inner hole process dimension and input the measured deviation into the specified tool wear compensation position;

[0097] N0680 G28 U0 W0 T0

[0098] N0685 T1212 Calculate and insert the tool length compensation after the change of wear in the current line;

[0099] Step 8: Complete on-site verification

[0100] If the process requirements are met, proceed to step nine; if the process requirements are not met, proceed to step one;

[0101] Step 9: Complete the tool operation instructions

[0102] According to the service life of the tool in actual processing, a tool use balance plan and tool use rules for the processing program are formulated. The balance plan includes tool types and usage quotas, and the tool use rules for the processing program include tool clamping length, tool handle corresponding program number information and technical requirements for use.

[0103] Step 10: Complete automated tool management

[0104] Solidify the types and consumption of machining tools. In view of the complex structure, multiple features and various types of machining tools of disc-type parts, according to the direct experience of using different tools accumulated in long-term machining, combined with quality and cost control requirements, select appropriate machining tools to lay the foundation for the solidification of machining parameters;

[0105] A tool life control program is compiled to automatically monitor the use of the tool through the system, and automatically determine whether the tool used in processing has reached the set tool life. When the set life is reached, the system disables the tool and automatically calls a new tool to continue processing, thereby realizing tool life management.

[0106] Tool life monitoring can be achieved by setting tool life parameters, compiling tool life control programs, and automatically monitoring tool usage through the machine tool control system. It can automatically determine whether the tool used in processing has reached the set tool life. When the set life is reached, the system disables the tool and automatically calls a new tool to continue processing, thereby achieving automatic tool life control. Through the research and utilization of tool life control functions, its control method has been mastered and applied to the full-program unmanned processing of typical parts;

[0107] Step 11: Complete batch application

[0108] After completing the above verification work and pre-batch production preparation, batch production can be carried out. After technical research, engineering application and system improvement, it has played a very significant role in optimizing CNC machining technology, improving the quality of CNC machining programs and product CNC machining quality, and improving the batch production capacity of engines;

[0109] Step 12: Complete process curing

[0110] Through batch production, the process is further solidified to ensure the stability of the process.

[0111] Through experience distillation and technology accumulation, the solidified process can be used as a template for parts of the same type, so that the process design of parts with similar features can be quickly carried out.

[0112] Applying mature processes to the manufacturing of similar parts can reduce the R&D and manufacturing costs of similar products and improve pre-manufacturing preparation efficiency.

Claims

1. An automated CNC machining process for aircraft engine turbine disk parts, characterized in that: The steps include: Step 1: Formulate the turbine disc process; conventional turbine disc processes include rough turning, semi-finishing turning, finishing turning, and finishing milling; Step 2: Complete the machine tool and software configuration, and determine the automated processing unit based on the principle of one-time positioning and clamping for processing multiple parts, mainly four-axis and five-axis machining centers and CNC vertical lathes; use computer-aided processing software for multi-axis CNC processing programming; Step 3: Complete the development of machine tools and software functions, mainly based on the requirements of automated CNC machining process to achieve high-quality and efficient machining; Step 4: Complete the tool holder selection and select the tool holder that is suitable for the part structure and material characteristics, based on the control principles of good quality, high efficiency and low cost; Step 5: Complete the optimization of the fixture, including structural and functional optimization. Based on the principle of optimal positioning accuracy and high clamping efficiency, the fixture adopts hydraulic clamping control to effectively control the positioning accuracy and improve the clamping efficiency. Step 6: Complete the NC program simulation optimization and use simulation technology to verify the NC process and optimization; Step 7: Complete the effect inspection. If the process meets the expected requirements and no better improvement direction can be found, proceed to step 8. Continue simulation optimization and proceed to step 6. Step 8: Complete the on-site verification. If the process requirements are met, proceed to step 9. If the process requirements are not met, proceed to step 1. Step nine, complete the preparation of tool operation instructions, formulate a tool use balance plan and tool use rules for the processing program based on tool life statistics, including the actual cutting time of the tool used on site; Step 10: Complete automated tool management, including tool type and consumption management, machine tool tool data management, and tool life management; Step 11: Complete the batch production application to meet the model batch production requirements; Step 12: Complete the process solidification, form a typical feature processing template, and promote it to the same type of parts.

2. The method for automated numerical control machining of aero-engine turbine disk parts according to claim 1, characterized in that: In step three, the development of machine tools and software functions supports the realization of automated CNC process, mainly including the development of part coordinate detection function to prevent machining coordinate system call errors; the development of spindle cutting power adaptive control function to prevent tool damage; the development of multiple high-level instructions to form composite functions for complex logical judgments in the machining process; the development of functional integration applications to achieve control of the machining process; the development of external program call functions to achieve minimum memory usage; and the development of on-machine measurement function applications for online measurement of machining centers and vertical lathes.

3. The method for automated numerical control machining of aircraft engine turbine disk parts according to claim 1, characterized in that: In step six, the simulation optimization of the CNC program is completed. First, the simulation processing environment is unified, including the tool, machine tool structure tree, 3D model, post-processing and machine tool control system configuration; the part tool change position and automatic tool compensation are set to perform automatic tool change processing, which reduces the risk of manual tool change and improves processing efficiency; the part detection position is set, and the infrared probe and control system measurement cycle program are used to formulate online measurement of features such as diameter and bevel points; the measurement program is compiled to realize automatic measurement of the processing process, monitor the part processing quality, and improve processing efficiency; the cutting force and processing deformation prediction, surface roughness prediction, and optimization of the CNC program are completed.

4. The method for automated numerical control machining of aircraft engine turbine disk parts according to claim 1, characterized in that: In step twelve, process solidification includes CNC machining process solidification and machine tool and clamping solidification; the processing template is to extract typical processing features in the process and promote them to the same type of parts.

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