Electrolytic arc milling composite CNC machine tool control method and system for casing machining

Abstract

This application relates to the technical field of machine tool control, and particularly to an electrolytic arc milling composite numerical control machine tool control method and system for casing machining. This application first starts the electrolyte supply, arc generation, high-pressure water jet, and ultrasonic vibration systems in sequence, obtains operation data, and calculates rough machining parameters; during rough machining, the machining gap, discharge state, and temperature are monitored in real time, and the correction value is calculated by comparing with the standard parameters; after rough machining is completed and the electrolytic arc milling device is removed, the feed speed and spindle speed are adjusted according to the correction value to obtain finish machining parameters; by electrolytically arc-etching materials and combining the synergistic effects of high-pressure water jets and ultrasonic vibrations, the efficient removal and precise control of super-difficult-to-machine materials such as titanium alloys and heat-resistant alloys during the machining process are realized, improving the machining efficiency and quality.

Description

Technical Field

[0001] The present application relates to the technical field of machine tool control, and particularly to an electrolytic arc milling composite numerical control machine tool control method and system for casing machining. Background Art

[0002] The casing is an important structural part of an aeroengine, and its machining quality directly affects the performance and reliability of the engine. With the rapid development of the aviation industry, the casing structure has become increasingly complex, and super-difficult-to-machine materials such as high-strength titanium alloys or heat-resistant hard alloys are used, which pose higher requirements for machining processes and equipment.

[0003] At present, the casing machining mainly adopts the numerical control milling process, which outputs large torque through a high-power spindle and removes materials at a low speed. To improve the machining efficiency, a multi-axis linkage machining method is adopted, and technologies such as special tools and intelligent machining path planning are combined.

[0004] When traditional numerical control milling is used to machine high-strength heat-resistant alloy casings, due to the high strength, low thermal conductivity, and high toughness of the materials, the tool wear is serious, the cutting force is large, the machining efficiency is low, and machining deformation is likely to occur, making it difficult to ensure the machining accuracy; this situation needs to be further improved. Summary of the Invention

[0005] In order to solve the problem that it is difficult to ensure the machining accuracy when existing numerical control milling is used to machine high-strength heat-resistant alloy casings, the present application provides an electrolytic arc milling composite numerical control machine tool control method and system for casing machining, and adopts the following technical solutions:

[0006] In the first aspect, the present application provides an electrolytic arc milling composite numerical control machine tool control method for casing machining, which is applied to an electrolytic arc milling composite numerical control machine tool. The electrolytic arc milling composite numerical control machine tool includes an electrolytic arc milling device detachably connected to the end of the spindle. The electrolytic arc milling device includes an electrolyte supply system, an arc generation system, a high-pressure water jet system, and an ultrasonic vibration system. The method includes the following steps:

[0007] Start the electrolyte supply system, the arc generation system, the high-pressure water jet system, and the ultrasonic vibration system in sequence, detect the parameters of each system, and obtain the system operation data;

[0008] Calculate the electrolytic arc milling rough machining parameters based on the system operation data;

[0009] According to the rough machining parameters, monitor the machining gap, the discharge state, and the machining area temperature in real time, and calculate the machining parameter correction value according to the deviation value between the monitoring result and the standard parameters;

[0010] After completing the rough machining of electrolytic arc milling, obtain the instruction that the removal of the electrolytic arc milling device is completed. Based on the machining parameter correction value, adjust the feed rate and spindle speed to obtain the CNC finishing parameters.

[0011] By adopting the above technical solution, the present application first starts each system in the order of electrolyte supply, arc generation, high-pressure water jet, and ultrasonic vibration, and obtains the system operation data through detection; then calculates the suitable rough machining parameters based on these data; during the rough machining process, the system monitors the machining gap, discharge state, and machining area temperature in real time, compares the monitoring results with the standard parameters, and calculates the parameter correction value; when the rough machining is completed, after the system receives the instruction that the removal of the electrolytic arc milling device is completed, it adjusts the feed rate and spindle speed according to the previously obtained correction value to obtain the machining parameters required for finishing; reduces the cutting force by electrolytic arc erosion of materials, and improves the chip removal effect by the synergistic effect of high-pressure water jet and ultrasonic vibration, realizing the precise control of the machining process, not only solving the problems existing in the traditional machining method, but also significantly improving the machining efficiency and machining quality.

[0012] Optionally, the method further includes the following steps:

[0013] According to the finishing parameters, perform CNC milling finishing and on-line detection to obtain the workpiece machining quality data;

[0014] Based on the workpiece machining quality data, calculate the compensation amount and perform compensation machining to obtain the final machining accuracy.

[0015] By adopting the above technical solution, the system performs CNC milling machining according to the calculated finishing parameters, and at the same time performs real-time on-line detection to obtain the machining quality data of the workpiece; based on the collected machining quality data, calculates the required compensation amount and performs compensation machining accordingly; not only makes full use of the machining parameter correction experience accumulated in the previous rough machining stage, but also can compensate for the errors occurring during the finishing process in a timely manner, so as to ensure that a high-precision machining finished product is finally obtained.

[0016] Optionally, according to the deviation value between the monitoring result and the standard parameter, calculate the machining parameter correction value, which specifically includes the following steps:

[0017] Obtain the machining characteristics of the casing, divide the machining area into a key area and a non-key area, the key area includes connecting holes, positioning reference surfaces, and sealing surfaces, and the non-key area includes ordinary planes, transition surfaces, and non-functional surfaces;

[0018] Monitor the machining gap deviation value, discharge state deviation value, and temperature deviation value of the key area and the non-key area respectively;

[0019] Calculate the first correction value for the critical area and the second correction value for the non-critical area according to the weight coefficients of the respective deviation values;

[0020] Based on the first correction value and the second correction value, obtain the machining parameter correction value.

[0021] By adopting the above technical solution, the present application divides the machining area into a critical area and a non-critical area; during the machining process, the system monitors these two types of areas respectively in a targeted manner, and real-time collects the deviation values of three key parameters: machining gap, discharge state, and temperature. Considering the functional characteristics and machining requirements of different areas, the system sets corresponding weight coefficients for each deviation value, and respectively obtains the first correction value for the critical area and the second correction value for the non-critical area through weighted calculation. Finally, the overall machining parameter correction value is obtained by integrating these two correction values; this not only ensures the machining accuracy of the critical functional parts but also improves the machining efficiency of the non-critical areas.

[0022] Optionally, the determination of the weight coefficients specifically includes the following steps:

[0023] According to the machining accuracy requirements of the critical area, set the first weight of the machining gap deviation value, the second weight of the discharge state deviation value, and the third weight of the temperature deviation value;

[0024] According to the machining efficiency requirements of the non-critical area, set the fourth weight of the machining gap deviation value, the fifth weight of the discharge state deviation value, and the sixth weight of the temperature deviation value.

[0025] By adopting the above technical solution, for the critical area, the system focuses on machining accuracy. Therefore, when setting the weight coefficients, it mainly considers the influence degrees of the machining gap deviation value, the discharge state deviation value, and the temperature deviation value on machining accuracy, and assigns the first weight, the second weight, and the third weight respectively; for the non-critical area, considering that machining efficiency is the main goal, the system correspondingly sets different fourth weights, fifth weights, and sixth weights, among which the discharge state deviation value related to the material removal rate will obtain a higher weight value; this weight distribution scheme based on regional characteristics and machining objectives enables the system to flexibly adjust the control strategy according to the specific requirements of different areas, thereby achieving the improvement of machining efficiency on the premise of ensuring machining quality.

[0026] Optionally, based on the machining parameter correction value, adjust the feed rate and spindle speed to obtain the NC precision machining parameters, specifically including the following steps:

[0027] According to the first correction value and the second correction value, evaluate the material removal status of the critical area and the non-critical area;

[0028] Based on the material removal status, calculate the finishing allowance required for the critical area and the finishing allowance required for the non-critical area;

[0029] Determine the corresponding spindle speed matching relationship and feed speed matching relationship according to the finishing allowances of each region;

[0030] Obtain the CNC finishing parameters according to the spindle speed matching relationship and the feed speed matching relationship.

[0031] By adopting the above technical solution, the application first evaluates the actual material removal conditions of the key regions and non-key regions according to the first correction value and the second correction value obtained in the rough machining stage; then, based on these evaluation results, calculates the finishing allowances required for each of the two types of regions; next, the system establishes the corresponding spindle speed matching relationship and feed speed matching relationship for different regions according to the calculated finishing allowances, realizing the differential setting of parameters; finally, based on these matching relationships, obtains the final CNC finishing parameters; by establishing the quantitative relationship between the material removal state and the machining parameters, the precise control of the finishing parameters is realized, which not only improves the machining efficiency but also ensures the machining quality of each functional region.

[0032] Optionally, according to the finishing parameters, perform CNC milling finishing and conduct on-line inspection to obtain the workpiece machining quality data, which specifically includes the following steps:

[0033] Detect the actual output values of the spindle speed and the feed speed according to the finishing parameters;

[0034] Real-time collect the spindle load and feed load data, and calculate the spindle speed fluctuation value, the feed speed fluctuation value and the cutting force fluctuation value;

[0035] Based on the spindle speed fluctuation value, the feed speed fluctuation value and the cutting force fluctuation value, obtain the workpiece surface quality, dimensional accuracy and machining efficiency data;

[0036] Obtain the workpiece machining quality data according to the surface quality, dimensional accuracy and machining efficiency data.

[0037] By adopting the above technical solution, the present application first detects the actual output values of the spindle speed and the feed speed in real time according to the set finish machining parameters to ensure the execution accuracy of the machining parameters. At the same time, the spindle load and the feed load data are continuously collected through a sensor network, and the spindle speed fluctuation value, the feed speed fluctuation value and the cutting force fluctuation value are calculated by using these data. These fluctuation values can directly reflect the stability of the machining process. Then, based on these three key fluctuation values, the system analyzes and calculates the surface quality, dimensional accuracy and machining efficiency data of the workpiece through the established mathematical model. Finally, these data are comprehensively processed to form a complete workpiece machining quality data set. Through multi-parameter real-time monitoring and correlation analysis, the mapping relationship between the machining process fluctuation and the machining quality is established, and the real-time evaluation of the machining quality is realized.

[0038] Optionally, based on the workpiece machining quality data, calculate the compensation amount and perform compensation machining to obtain the final machining accuracy, which specifically includes the following steps:

[0039] Determine the matching ratio range of the spindle speed and the feed speed according to the workpiece machining quality data;

[0040] Calculate the parameter compensation amount based on the matching ratio range and the preset machining quality requirements;

[0041] Dynamically adjust the spindle speed and the feed speed according to the parameter compensation amount to obtain the compensation machining parameters;

[0042] Perform compensation machining to obtain the final machining accuracy.

[0043] By adopting the above technical solution, the system first analyzes the workpiece machining quality data, and determines the best matching ratio range of the spindle speed and the feed speed through mathematical modeling. Then, the system compares and analyzes this matching ratio range with the preset machining quality requirements to calculate the specific parameter compensation amount. Next, the system adjusts the combination of the spindle speed and the feed speed in real time according to the calculated compensation amount to generate the final compensation machining parameters. Finally, perform compensation machining, and obtain the required machining accuracy through the precisely controlled compensation process, which not only ensures the accuracy of the compensation machining, but also improves the controllability of the compensation process.

[0044] In a second aspect, the present application provides an electrolytic arc milling composite numerical control machine tool control system for casing machining, including an electrolytic arc milling composite numerical control machine tool, and the electrolytic arc milling composite numerical control machine tool includes an electrolytic arc milling device detachably connected to the spindle end, and the electrolytic arc milling device includes:

[0045] An electrolyte supply system for providing electrolyte;

[0046] An arc generation system for generating an arc;

[0047] A high-pressure water jet system for generating a high-pressure jet;

[0048] An ultrasonic vibration system for generating ultrasonic vibrations;

[0049] A control unit for sequentially starting an electrolyte supply system, an arc generation system, a high-pressure water jet system, and an ultrasonic vibration system and detecting system parameters to obtain system operation data;

[0050] A parameter calculation unit for calculating rough electrolytic arc milling parameters based on the system operation data;

[0051] A monitoring unit for real-time monitoring of the machining gap, discharge state, and machining area temperature;

[0052] A correction unit for calculating a machining parameter correction value based on the deviation value between the monitoring result and the standard parameter;

[0053] A parameter adjustment unit for adjusting the feed speed and spindle speed based on the machining parameter correction value after obtaining the instruction for the completion of the removal of the electrolytic arc milling device to obtain NC finishing parameters.

[0054] Optionally, the system further includes:

[0055] A machining unit for performing NC milling finishing according to the finishing parameters;

[0056] A detection unit for performing on-line detection to obtain workpiece machining quality data;

[0057] A compensation unit for calculating a compensation amount based on the workpiece machining quality data and performing compensation machining to obtain the final machining accuracy.

[0058] Optionally, the correction unit includes:

[0059] An area division sub-unit for obtaining the machining features of the casing and dividing the machining area into a key area and a non-key area, where the key area includes connection holes, positioning reference surfaces, and sealing surfaces, and the non-key area includes ordinary planes, transition surfaces, and non-functional surfaces;

[0060] A monitoring sub-unit for respectively monitoring the machining gap deviation value, discharge state deviation value, and temperature deviation value of the key area and the non-key area;

[0061] A calculation sub-unit for calculating a first correction value for the key area and a second correction value for the non-key area according to the weight coefficients of the respective deviation values;

[0062] A parameter correction sub-unit for obtaining a machining parameter correction value based on the first correction value and the second correction value.

[0063] In summary, the present application includes at least one of the following beneficial technical effects:

[0064] The present application first starts each system in the order of electrolyte supply, arc generation, high-pressure water jet, and ultrasonic vibration, and obtains system operation data through detection; then calculates suitable rough machining parameters based on these data; during rough machining, the system monitors the machining gap, discharge state, and machining area temperature in real time, compares the monitoring results with standard parameters, and calculates parameter correction values; when rough machining is completed, after the system receives the instruction that the electrolytic arc milling device has been removed, it adjusts the feed speed and spindle speed according to the correction values obtained previously to obtain the machining parameters required for finish machining; improves efficiency by electrolytic arc erosion of materials, and improves the chip removal effect by the synergistic effect of high-pressure water jet and ultrasonic vibration, realizing precise control of the machining process, not only solving the problems existing in traditional machining methods, but also significantly improving machining efficiency and machining quality;

[0065] The system performs CNC milling machining according to the calculated finish machining parameters, and at the same time performs real-time online detection to obtain the machining quality data of the workpiece; based on the collected machining quality data, calculates the required compensation amount, and performs compensation machining accordingly; not only makes full use of the machining parameter correction experience accumulated in the previous rough machining stage, but also can timely compensate for the errors occurring during finish machining, thus ensuring the final high-precision machining finished product;

[0066] The present application divides the machining area into a key area and a non-key area; during machining, the system monitors these two types of areas respectively, and collects the deviation values of three key parameters: machining gap, discharge state, and temperature in real time. Considering the functional characteristics and machining requirements of different areas, the system sets corresponding weight coefficients for each deviation value, and respectively obtains the first correction value of the key area and the second correction value of the non-key area through weighted calculation, and finally obtains the overall machining parameter correction value by integrating these two correction values; not only ensures the machining accuracy of key functional parts, but also improves the machining efficiency of non-key areas. Brief Description of the Drawings

[0067] Figure 1 is a flow chart of the control method of the electrolytic arc milling composite CNC machine tool for casing machining in an embodiment of the present application;

[0068] Figure 2 is a flow chart of performing compensation machining in the control method of the electrolytic arc milling composite CNC machine tool for casing machining in an embodiment of the present application;

[0069] Figure 3 is a flow chart of step S300 in the control method of the electrolytic arc milling composite CNC machine tool for casing machining in an embodiment of the present application;

[0070] Figure 4 It is a schematic flow chart of step S330 in the control method of the electrolytic arc milling composite numerical control machine tool for casing machining according to an embodiment of the present application;

[0071] Figure 5 It is a schematic flow chart of step S400 in the control method of the electrolytic arc milling composite numerical control machine tool for casing machining according to an embodiment of the present application;

[0072] Figure 6 It is a schematic flow chart of step S500 in the control method of the electrolytic arc milling composite numerical control machine tool for casing machining according to an embodiment of the present application;

[0073] Figure 7 It is a schematic flow chart of step S600 in the control method of the electrolytic arc milling composite numerical control machine tool for casing machining according to an embodiment of the present application;

[0074] Figure 8 It is a schematic diagram of the modules of the control system of the electrolytic arc milling composite numerical control machine tool for casing machining according to an embodiment of the present application. Detailed implementation manners

[0075] The terms used in the following embodiments of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in the specification and appended claims of the present application, the singular forms "a", "an", "the", "above-mentioned", "said", and "this" are also intended to include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used in the present application refers to any or all possible combinations including one or more of the listed items.

[0076] Hereinafter, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as implying or suggesting relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the embodiments of the present application, unless otherwise specified, the meaning of "a plurality" is two or more.

[0077] The following further describes the embodiments of the present application in detail with reference to the accompanying drawings of the specification.

[0078] In a first aspect, the present application provides a control method for an electrolytic arc milling composite numerical control machine tool for casing machining, which is applied to an electrolytic arc milling composite numerical control machine tool. The electrolytic arc milling composite numerical control machine tool includes an electrolytic arc milling device detachably connected to the end of the main shaft. The electrolytic arc milling device includes an electrolyte supply system, an arc generation system, a high-pressure water jet system, and an ultrasonic vibration system. Referring to Figure 1 , the method includes the following steps:

[0079] S100. Sequentially start the electrolyte supply system, arc generation system, high-pressure water jet system, and ultrasonic vibration system, detect the parameters of each system, and obtain the system operation data.

[0080] In this embodiment, the electrolyte supply system is used to provide an electrolyte with a specific concentration to achieve electrochemical etching; the arc generation system generates a high-temperature arc through the discharge between the electrode and the workpiece; the high-pressure water jet system generates a directional high-pressure liquid flow for flushing the machining area; the ultrasonic vibration system provides a micron-level vibration for the tool to improve the cutting conditions.

[0081] Specifically, the system sequentially starts each subsystem at preset time intervals: first, start the electrolyte supply system and wait for the flow rate to stabilize; when the machining area is filled with the electrolyte, start the arc generation system and adjust it to the target voltage; after a preset delay, start the high-pressure water jet system; finally, turn on the ultrasonic vibration system. Collect the operation parameters of each system through a distributed sensor network, including data such as electrolyte pressure, conductivity, arc current, jet pressure, and vibration amplitude, and establish a system operation state data set.

[0082] S200. Calculate the rough machining parameters of electrolytic arc milling based on the system operation data.

[0083] In this embodiment, the rough machining parameters of electrolytic arc milling include feed rate, spindle speed, electrolytic voltage, jet pressure, electrolyte flow rate, and ultrasonic vibration frequency.

[0084] Specifically, the system performs parameter matching based on a pre-established process parameter database and combines the operation data obtained in the previous step. First, obtain a basic parameter combination by looking up a table, and then fine-tune the parameters according to the measured system response characteristics. For example, when it is detected that the electrolyte conductivity deviates from the standard value, the system automatically adjusts the feed rate according to a preset correction rule; when the discharge energy is unstable, the electrolytic voltage value is adjusted accordingly to ensure the stability of the machining process.

[0085] S300. According to the rough machining parameters, monitor the machining gap, discharge state, and machining area temperature in real time, and calculate the machining parameter correction value based on the deviation value between the monitoring result and the standard parameters.

[0086] In this embodiment, the machining gap refers to the actual distance between the electrode and the workpiece surface, the discharge state includes discharge frequency, discharge duration, discharge current, and arc voltage, and the machining area temperature reflects the degree of local heat accumulation.

[0087] Specifically, a multi-sensor array is used to monitor the machining status in real time: the machining gap is measured by a capacitive sensor; a high-speed sampling circuit is used to collect the characteristics of discharge signals, including current waveforms, voltage waveforms, and discharge frequency distributions; an infrared thermometer is used to monitor the temperature field distribution. The system compares these real-time data with preset standard parameters, and calculates the corresponding correction factors according to the deviation degree for subsequent parameter adjustment.

[0088] S400. After the rough machining of electrolytic arc milling is completed, obtain the instruction that the electrolytic arc milling device has been removed. Based on the corrected machining parameters, adjust the feed rate and spindle speed to obtain the CNC finishing machining parameters.

[0089] In this embodiment, the instruction that the electrolytic arc milling device has been removed refers to the status signal that the equipment confirms that the electrolyte supply pipeline, electrode wires, high-pressure water pipe, and ultrasonic vibrator have been safely removed. The CNC finishing machining parameters include spindle speed, feed rate, cutting depth, and tool feed angle.

[0090] Specifically, after receiving the removal completion signal, the system determines the finishing machining parameters by looking up the preset parameter mapping table according to the correction values obtained previously. When the rough machining correction value indicates that the material erosion effect is good, the system will correspondingly adjust the ratio relationship between the feed rate and the spindle speed, and at the same time optimize the cutting depth and feed angle to achieve the optimal machining effect.

[0091] In one embodiment, referring to Figure 2 , the method further includes the following steps:

[0092] S500. According to the finishing machining parameters, perform CNC milling finishing and conduct on-line inspection to obtain the workpiece machining quality data.

[0093] In this embodiment, the finishing machining parameters refer to the optimized machining parameters obtained through the previous machining process, including spindle speed, feed rate, cutting depth, and feed angle. The workpiece machining quality data includes surface roughness, dimensional accuracy, form and position tolerances, surface integrity, and machining stress. On-line inspection refers to the process of real-time collecting machining status information during machining.

[0094] Specifically, the system first performs CNC milling based on the finishing machining parameters. During machining, real-time monitoring is carried out through a pre-established sensor detection network: a displacement sensor is used to monitor dimensional changes, a force sensor is used to detect the magnitude of the cutting force, a vibration sensor is used to collect machining vibration signals, and a temperature sensor is used to monitor the machining temperature. By comparing with the preset process quality standards through a look-up table method, a workpiece machining quality evaluation index is generated.

[0095] S600. Based on the workpiece machining quality data, calculate the compensation amount and perform compensation machining to obtain the final machining accuracy.

[0096] In this embodiment, the compensation amount refers to the correction value of the machining parameters that need to be adjusted to improve the machining accuracy, including tool position compensation, feed speed compensation, spindle speed compensation, and cutting depth compensation. The final machining accuracy refers to the various quality indicators of the workpiece after all compensated machining is completed.

[0097] Specifically, the system adopts a hierarchical compensation strategy: First, a linear compensation mapping table is established, and the position compensation amount is quickly calculated based on the dimensional deviation in the workpiece machining quality data; for the form and position tolerance deviation, a pre-trained compensation model is used to calculate the correction value of the feed parameters; for surface quality problems, the adjustment amounts of the speed and cutting depth are determined by searching the standard process database.

[0098] In one embodiment, referring to Figure 3 , in step S300, according to the deviation value between the monitoring result and the standard parameter, the correction value of the machining parameter is calculated, which specifically includes the following steps:

[0099] S310. Obtain the machining features of the casing, and divide the machining area into key areas and non-key areas.

[0100] Among them, the key areas include connecting holes, positioning reference surfaces, and sealing surfaces, and the non-key areas include ordinary planes, transition surfaces, and non-functional surfaces.

[0101] In this embodiment, the machining features of the casing refer to the machining requirements and accuracy grades of different functional surfaces on the casing parts.

[0102] Specifically, the system first calls the pre-established casing feature recognition database and identifies the machining area through feature matching methods. For the connecting hole feature, the system identifies the diameter, depth, and position tolerance requirements; for the positioning reference surface, it identifies the flatness and roughness indexes; for the sealing surface, it identifies the surface integrity requirements. Using a geometric feature extraction algorithm, different feature surfaces in the CAD model are marked and divided into key areas and non-key areas according to their functional attributes.

[0103] S320. Monitor the machining gap deviation value, discharge state deviation value, and temperature deviation value of the key area and the non-key area respectively.

[0104] In this embodiment, the machining gap deviation value refers to the difference between the actual machining gap and the set value. The discharge state deviation value includes discharge frequency deviation, discharge duration deviation, discharge current deviation, and arc voltage deviation. The temperature deviation value refers to the difference between the actual temperature of the machining area and the ideal temperature.

[0105] Specifically, the system monitors the area through a mobile measuring device. The device includes a capacitive sensor for gap measurement, a set of discharge parameter acquisition circuits, and an infrared temperature measurement probe. During the processing, the system collects monitoring data in different areas according to the pre-planned measuring point distribution scheme. For key areas, the system increases the sampling frequency and the density of measuring points; for non-critical areas, a conventional sampling scheme with a lower frequency is adopted. The monitoring data is recorded through a preset data acquisition program, and the deviation values of various parameters are determined by the interval judgment method.

[0106] S330. Calculate the first correction value for the key area and the second correction value for the non-critical area according to the weight coefficients of the respective deviation values.

[0107] In this embodiment, the weight coefficient reflects the influence degree of different deviation values on the processing quality. The first correction value is the comprehensive correction amount obtained by weighted calculation of various deviations in the key area, and the second correction value is the weighted correction amount of various deviations in the non-critical area.

[0108] Specifically, the system determines the weight coefficients of the respective deviation values according to a pre-established weight distribution table.

[0109] S340. Obtain the processing parameter correction value based on the first correction value and the second correction value.

[0110] The processing parameter correction value refers to the final process parameter adjustment amount calculated according to the correction values of the two areas, including the feed speed correction amount, the spindle speed correction amount, the cutting depth, and the tool feed angle correction amount.

[0111] Specifically, the system adopts a zoning compensation strategy: first, establish a regional priority table to determine the principle of preferential use of the correction value in the key area; then, by looking up the correction value mapping table, convert the correction values of the two areas into specific parameter adjustment amounts.

[0112] In one embodiment, referring to Figure 4 , in step S330, the determination of the weight coefficient specifically includes the following steps:

[0113] S331. Set the first weight of the machining gap deviation value, the second weight of the discharge state deviation value, and the third weight of the temperature deviation value according to the machining accuracy requirements of the key area.

[0114] Specifically, the system determines the weight values by looking up a pre-established mapping table of factors affecting precision. This mapping table is summarized based on a large amount of machining test data and records the corresponding relationships between different deviation values and machining precision indicators. When machining connecting holes, the system identifies the dimensional accuracy and positional tolerance requirements, and looks up the table to obtain the ratio of the three weight values as 5:3:2; when machining the sealing surface, based on its surface integrity requirements, the weight ratio is adjusted to 4:4:2. The system uses the linear interpolation method to calculate the specific weight values according to the precision requirements of different features.

[0115] S332. Set the fourth weight of the machining gap deviation value, the fifth weight of the discharge state deviation value, and the sixth weight of the temperature deviation value according to the machining efficiency requirements of the non-critical area.

[0116] Specifically, the system uses an efficiency optimization database to determine the weight values. The database records the machining efficiency indicators under different combinations of process parameters, and establishes the correlation between the deviation values and the efficiency indicators through statistical analysis methods. When machining ordinary planes, the system identifies the material removal rate requirements, and looks up the table to obtain the ratio of the three weight values as 3:4:3; when machining transition surfaces, based on the machining time requirements, the weight ratio is adjusted to 2:5:3. For different machining task characteristics, the system quickly determines the appropriate weight configuration by looking up the table.

[0117] In one embodiment, referring to Figure 5 , in step S400, based on the machining parameter correction values, adjust the feed rate and spindle speed to obtain the CNC finishing parameters, which specifically include the following steps:

[0118] S410. Evaluate the material removal status of the critical area and the non-critical area according to the first correction value and the second correction value.

[0119] Among them, the first correction value and the second correction value reflect the adjustment range of the process parameters during rough machining and are used to evaluate the material removal effect.

[0120] Specifically, the system establishes a material status evaluation table to establish the corresponding relationship between the correction value size and the material removal status. When the correction value fluctuates within the normal range, it indicates that the material removal status is stable; when the correction value fluctuates greatly, it means that the material removal in the local area is uneven.

[0121] S420. Calculate the finishing allowance required for the critical area and the finishing allowance required for the non-critical area based on the material removal status.

[0122] Specifically, the system determines the reference allowance value by searching the pre-established allowance distribution database. For critical areas, when the material removal state is good, the system selects the standard allowance value; when local under-etching is detected, the allowance is appropriately increased. For non-critical areas, mainly considering the machining efficiency, the minimum necessary allowance is determined by linear calculation.

[0123] S430. Determine the corresponding spindle speed matching relationship and feed speed matching relationship according to the finish machining allowances of each area.

[0124] Among them, the spindle speed matching relationship refers to the optimal spindle speed selection rule under different finish machining allowances, and the feed speed matching relationship refers to the feed speed selection rule that matches the spindle speed.

[0125] S440. Obtain the CNC finish machining parameters according to the spindle speed matching relationship and the feed speed matching relationship.

[0126] Specifically, the system calculates the final combination of finish machining parameters based on the matching relationship between the spindle speed and the feed speed, in combination with the pre-established cutting parameter optimization model. The model inputs include the allowance distribution and the material state evaluation result; the output is the specific machining parameter value. For example, when machining a sealing surface, the system selects a lower feed rate and cutting depth combination according to its high-precision requirements; when machining a common plane, a larger feed rate is selected to improve the efficiency.

[0127] In one embodiment, referring to Figure 6 , in step S500, according to the finish machining parameters, perform CNC milling finish machining and conduct on-line inspection to obtain the workpiece machining quality data, which specifically includes the following steps:

[0128] S510. Detect the actual output values of the spindle speed and the feed speed according to the finish machining parameters.

[0129] In this embodiment, the actual output values refer to the actual operating parameters when the CNC system executes the machining instructions, including the spindle motor speed, the feed motor speed, the spindle current, and the feed current.

[0130] Specifically, the system collects the motor operating state data through the parameter reading interface built in the CNC system. Establish a simple parameter monitoring table to record the corresponding relationship between the set value and the actual value. When the deviation between the actual output value and the set value is detected to exceed 10%, the system records the machining position information at that moment.

[0131] S520. Real-time collect the spindle load and feed load data, and calculate the spindle speed fluctuation value, the feed speed fluctuation value, and the cutting force fluctuation value.

[0132] In this embodiment, the spindle load refers to the real-time power consumption of the spindle motor, and the feed load refers to the real-time current value of the feed motor. The fluctuation value refers to the change range of these parameters during the machining process, reflecting the stability of the machining process.

[0133] Specifically, the system uses the sliding window method to calculate the parameter fluctuation characteristics in real time. Through the pre-established fluctuation characteristic database, the collected load data is converted into a standardized fluctuation value. The sampling period of the spindle speed fluctuation value is 0.1 second, the sampling period of the feed speed fluctuation value is 0.2 seconds, and the cutting force fluctuation value is indirectly calculated through the motor current, with a sampling period of 0.1 second.

[0134] S530. Based on the spindle speed fluctuation value, the feed speed fluctuation value, and the cutting force fluctuation value, obtain the workpiece surface quality, dimensional accuracy, and machining efficiency data.

[0135] In this embodiment, the workpiece surface quality includes surface roughness and surface integrity, the dimensional accuracy includes dimensional deviation and geometric tolerance, and the machining efficiency includes material removal rate and machining time.

[0136] Specifically, the system establishes a machining quality evaluation mapping table to establish a corresponding relationship between different combinations of fluctuation values and machining quality indicators. When the spindle speed fluctuation value is less than 5%, the system determines that the surface quality is good; when the feed speed fluctuation value is greater than 15%, the system warns that there may be dimensional accuracy problems; when the cutting force fluctuation value changes suddenly, record the machining efficiency data at this position.

[0137] S540. According to the surface quality, dimensional accuracy, and machining efficiency data, obtain the workpiece machining quality data.

[0138] In this embodiment, the workpiece machining quality data is a comprehensive evaluation of the overall machining state of the workpiece, including quality grade, defect type, machining stability, and surface integrity.

[0139] Specifically, the system uses a hierarchical evaluation method to integrate the index data. By looking up the quality evaluation standard table, the detection results of surface quality, dimensional accuracy, and machining efficiency are converted into standardized evaluation scores. For key functional surfaces, the system focuses on surface quality and dimensional accuracy indicators; for ordinary structural surfaces, the machining efficiency indicator is mainly considered.

[0140] In one embodiment, referring to Figure 7 , in step S600, based on the workpiece machining quality data, calculate the compensation amount and perform compensation machining to obtain the final machining accuracy, which specifically includes the following steps:

[0141] S610. According to the workpiece machining quality data, determine the matching ratio range of the spindle speed and the feed speed.

[0142] Among them, the matching ratio range refers to the reasonable matching interval of the spindle speed and the feed speed, which is used to ensure the stability of the cutting process.

[0143] Specifically, the system first establishes a parameter matching database to record the optimal parameter ratios under different machining conditions. When the surface roughness is detected to be out of tolerance, the system looks up the table to obtain the applicable lower ratio range; when the dimensional accuracy is insufficient, a higher ratio range is selected.

[0144] S620. Calculate the parameter compensation amount based on the matching ratio range and the preset machining quality requirements.

[0145] In this embodiment, the parameter compensation amount includes two basic amounts: the spindle speed compensation amount and the feed speed compensation amount. The system selects the corresponding compensation strategy according to the characteristics of different machining areas.

[0146] S630. Dynamically adjust the spindle speed and the feed speed according to the parameter compensation amount to obtain the compensated machining parameters.

[0147] Among them, the compensated machining parameters refer to the optimized parameter combination after dynamic adjustment.

[0148] Specifically, the system establishes a parameter adjustment rule table to specify the step size and timing of parameter adjustment. When it is necessary to increase the spindle speed, a stepped adjustment method is adopted, and the increase amplitude each time does not exceed 5%; when it is necessary to reduce the feed speed, a progressive adjustment method is adopted, and the adjustment interval is not less than 2 seconds. Through this stable adjustment method, the stability of the compensation process is ensured.

[0149] S640. Perform compensated machining to obtain the final machining accuracy.

[0150] It should be understood that the magnitudes of the sequence numbers of the steps in the above embodiments do not mean the order of execution. The execution order of each process should be determined according to its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

[0151] In a second aspect, the present application provides an electrolytic arc milling composite numerical control machine tool control system for casing machining. Below, in combination with the above-mentioned electrolytic arc milling composite numerical control machine tool control method for casing machining, the electrolytic arc milling composite numerical control machine tool control system of the present application will be described.

[0152] Refer to Figure 8 , an electrolytic arc milling composite numerical control machine tool control system for casing machining includes an electrolytic arc milling composite numerical control machine tool. The electrolytic arc milling composite numerical control machine tool includes an electrolytic arc milling device detachably connected to the end of the spindle. The electrolytic arc milling device includes:

[0153] An electrolyte supply system for providing electrolyte;

[0154] An arc generation system for generating an arc;

[0155] A high-pressure water jet system for generating a high-pressure water jet;

[0156] An ultrasonic vibration system for generating ultrasonic vibrations;

[0157] A control unit for sequentially starting an electrolyte supply system, an arc generation system, a high-pressure water jet system, and an ultrasonic vibration system and detecting system parameters to obtain system operation data;

[0158] A parameter calculation unit for calculating rough electrolytic arc milling parameters based on the system operation data;

[0159] A monitoring unit for real-time monitoring of the machining gap, discharge state, and machining area temperature;

[0160] A correction unit for calculating a machining parameter correction value according to the deviation value between the monitoring result and the standard parameter;

[0161] A parameter adjustment unit for adjusting the feed speed and spindle speed based on the machining parameter correction value after obtaining the instruction for the completion of the removal of the electrolytic arc milling device to obtain NC finishing parameters.

[0162] In one embodiment, the system further includes:

[0163] A machining unit for performing NC milling finishing according to the finishing parameters;

[0164] A detection unit for performing on-line detection to obtain workpiece machining quality data;

[0165] A compensation unit for calculating a compensation amount based on the workpiece machining quality data and performing compensation machining to obtain the final machining accuracy.

[0166] In one embodiment, the correction unit includes:

[0167] A region division sub-unit for obtaining the machining features of the casing and dividing the machining area into a key region and a non-key region. The key region includes connection holes, positioning reference surfaces, and sealing surfaces, and the non-key region includes ordinary planes, transition surfaces, and non-functional surfaces;

[0168] A monitoring sub-unit for respectively monitoring the machining gap deviation value, discharge state deviation value, and temperature deviation value of the key region and the non-key region;

[0169] A calculation sub-unit for calculating a first correction value for the key region and a second correction value for the non-key region according to the weight coefficients of the respective deviation values;

[0170] A parameter correction subunit, configured to obtain a machining parameter correction value based on a first correction value and a second correction value.

[0171] In one embodiment, the calculation subunit further includes:

[0172] A first setting module, configured to set a first weight of a machining gap deviation value, a second weight of a discharge state deviation value, and a third weight of a temperature deviation value according to the machining accuracy requirements of a key area;

[0173] A second setting module, configured to set a fourth weight of a machining gap deviation value, a fifth weight of a discharge state deviation value, and a sixth weight of a temperature deviation value according to the machining efficiency requirements of a non-key area.

[0174] In one embodiment, the parameter adjustment unit includes:

[0175] An evaluation subunit, configured to evaluate the material removal states of the key area and the non-key area according to the first correction value and the second correction value;

[0176] A finishing allowance calculation subunit, configured to calculate the finishing allowance required for the key area and the finishing allowance required for the non-key area based on the material removal states;

[0177] A matching relationship subunit, configured to determine the corresponding spindle speed matching relationship and feed speed matching relationship according to the finishing allowances of each area;

[0178] A parameter determination subunit, configured to obtain the numerical control finishing parameters according to the spindle speed matching relationship and the feed speed matching relationship.

[0179] In one embodiment, the detection unit includes:

[0180] A parameter detection subunit, configured to detect the actual output values of the spindle speed and the feed speed according to the finishing parameters;

[0181] A data acquisition subunit, configured to collect spindle load and feed load data in real time, and calculate the spindle speed fluctuation value, the feed speed fluctuation value, and the cutting force fluctuation value;

[0182] A data acquisition subunit, configured to obtain workpiece surface quality, dimensional accuracy, and machining efficiency data based on the spindle speed fluctuation value, the feed speed fluctuation value, and the cutting force fluctuation value;

[0183] A quality evaluation subunit, configured to obtain workpiece machining quality data according to the surface quality, dimensional accuracy, and machining efficiency data.

[0184] In one embodiment, the compensation unit includes:

[0185] A ratio determination subunit, configured to determine a matching ratio range of a spindle speed to a feed speed according to workpiece machining quality data;

[0186] A compensation calculation subunit, configured to calculate a parameter compensation amount based on the matching ratio range and a preset machining quality requirement;

[0187] A parameter adjustment subunit, configured to dynamically adjust the spindle speed and the feed speed according to the parameter compensation amount to obtain compensated machining parameters;

[0188] A compensation execution subunit, configured to execute compensated machining to obtain a final machining accuracy.

[0189] The above are all preferred embodiments of the present application, and do not limit the protection scope of the present application accordingly. Therefore, all equivalent changes made according to the structure, shape, and principle of the present application shall be covered within the protection scope of the present application.

Claims

1. A control method for an electrolytic arc milling composite CNC machine tool for casing machining, characterized in that, Applied to an electrolytic arc milling compound numerical control machine tool, the electrolytic arc milling compound numerical control machine tool includes an electrolytic arc milling device detachably connected to the end of the main shaft. The electrolytic arc milling device includes an electrolyte supply system, an arc generation system, a high-pressure water jet system, and an ultrasonic vibration system. The method includes the following steps: Start the electrolyte supply system, arc generation system, high-pressure water jet system, and ultrasonic vibration system in sequence, detect the parameters of each system, and obtain the system operation data; Based on the system operation data, calculate the rough machining parameters of electrolytic arc milling; According to the rough machining parameters, monitor the machining gap, discharge state, and machining area temperature in real time, and calculate the machining parameter correction value according to the deviation value between the monitoring result and the standard parameters; After completing the rough machining of electrolytic arc milling, obtain the instruction to complete the removal of the electrolytic arc milling device, and based on the machining parameter correction value, adjust the feed speed and spindle speed to obtain the numerical control finish machining parameters; Among them, calculating the machining parameter correction value according to the deviation value between the monitoring result and the standard parameters specifically includes the following steps: Obtain the machining characteristics of the casing, divide the machining area into a key area and a non-key area. The key area includes connection holes, positioning reference surfaces, and sealing surfaces, and the non-key area includes ordinary planes, transition surfaces, and non-functional surfaces; Monitor the machining gap deviation value, discharge state deviation value, and temperature deviation value of the key area and non-key area respectively; Calculate the first correction value of the key area and the second correction value of the non-key area according to the weight coefficients of each deviation value; Based on the first correction value and the second correction value, obtain the machining parameter correction value.

2. The control method of the electro-chemical arc milling composite CNC machine tool for casing machining according to claim 1, wherein, The method further includes the following steps: According to the finish machining parameters, perform numerical control milling finish machining and on-line detection to obtain the workpiece machining quality data; Based on the workpiece machining quality data, calculate the compensation amount and perform compensation machining to obtain the final machining accuracy.

3. The electrolytic arc milling composite CNC machine tool control method for casing machining according to claim 1, characterized in that The determination of the weight coefficient specifically includes the following steps: According to the machining accuracy requirements of the key area, set the first weight of the machining gap deviation value, the second weight of the discharge state deviation value, and the third weight of the temperature deviation value; According to the machining efficiency requirements of the non-key area, set the fourth weight of the machining gap deviation value, the fifth weight of the discharge state deviation value, and the sixth weight of the temperature deviation value.

4. The control method of the electro-chemical arc milling composite numerical control machine tool for casing machining according to claim 1, wherein, Based on the machining parameter correction value, adjusting the feed speed and spindle speed to obtain the numerical control finish machining parameters specifically includes the following steps: According to the first correction value and the second correction value, evaluate the material removal state of the key area and the non-key area; Based on the material removal state, calculate the finish machining allowance required for the key area and the finish machining allowance required for the non-key area; According to the finish machining allowance of each area, determine the corresponding spindle speed matching relationship and feed speed matching relationship; According to the spindle speed matching relationship and the feed speed matching relationship, obtain the numerical control finish machining parameters.

5. The control method of the electrolytic arc milling composite CNC machine tool for casing machining according to claim 2, wherein, According to the finish machining parameters, performing numerical control milling finish machining and on-line detection to obtain the workpiece machining quality data specifically includes the following steps: According to the finish machining parameters, detect the actual output values of the spindle speed and the feed speed; Collect the spindle load and feed load data in real time, and calculate the spindle speed fluctuation value, feed speed fluctuation value, and cutting force fluctuation value; Based on the spindle speed fluctuation value, feed speed fluctuation value, and cutting force fluctuation value, obtain the workpiece surface quality, dimensional accuracy, and machining efficiency data; According to the surface quality, dimensional accuracy, and machining efficiency data, obtain the workpiece machining quality data.

6. The electrolytic arc milling composite CNC machine tool control method for casing machining according to claim 5, characterized in that Based on the workpiece machining quality data, calculate the compensation amount and perform compensation machining to obtain the final machining accuracy, which specifically includes the following steps: According to the workpiece machining quality data, determine the matching ratio range of the spindle speed and feed speed; Based on the matching ratio range and the preset machining quality requirements, calculate the parameter compensation amount; According to the parameter compensation amount, dynamically adjust the spindle speed and feed speed to obtain the compensation machining parameters; Perform compensation machining to obtain the final machining accuracy.

7. An electrolytic arc milling composite CNC machine tool control system for casing machining, characterized in that, It includes an electrolytic arc milling composite CNC machine tool, and the electrolytic arc milling composite CNC machine tool includes an electrolytic arc milling device detachably connected to the spindle end. The electrolytic arc milling device includes: An electrolyte supply system for providing electrolyte; An arc generation system for generating an arc; A high-pressure water jet system for generating a high-pressure jet; An ultrasonic vibration system for generating ultrasonic vibration; A control unit for sequentially starting the electrolyte supply system, arc generation system, high-pressure water jet system, and ultrasonic vibration system and detecting system parameters to obtain system operation data; A parameter calculation unit for calculating the rough machining parameters of electrolytic arc milling based on the system operation data; A monitoring unit for real-time monitoring of the machining gap, discharge state, and machining area temperature; A correction unit for calculating the machining parameter correction value according to the deviation value between the monitoring result and the standard parameter, including: A region division sub-unit for obtaining the machining characteristics of the casing, dividing the machining area into a key area and a non-key area. The key area includes connection holes, positioning reference surfaces, and sealing surfaces, and the non-key area includes ordinary planes, transition surfaces, and non-functional surfaces; A monitoring sub-unit for respectively monitoring the machining gap deviation value, discharge state deviation value, and temperature deviation value of the key area and the non-key area; A calculation sub-unit for calculating the first correction value of the key area and the second correction value of the non-key area according to the weight coefficients of the deviation values; A parameter correction sub-unit for obtaining the machining parameter correction value based on the first correction value and the second correction value; A parameter adjustment unit for adjusting the feed speed and spindle speed based on the machining parameter correction value after obtaining the instruction to complete the removal of the electrolytic arc milling device to obtain the CNC finish machining parameters.

8. The electrolytic arc milling composite CNC machine tool control system for casing machining according to claim 7, wherein The system further includes: A machining unit for performing CNC milling finish machining according to the finish machining parameters; A detection unit for performing on-line detection to obtain the workpiece machining quality data; A compensation unit for calculating the compensation amount based on the workpiece machining quality data and performing compensation machining to obtain the final machining accuracy.

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