Machine tool processing optimization method and system based on multi-process coordination

Abstract

This invention discloses a machine tool machining optimization method and system based on multi-process coordination, belonging to the field of machine tool machining. The method includes: analyzing the structural machining requirements based on the irregular surface geometric features of the nut part; matching the structural machining requirements with various optimized process control strategies to determine the optimized process control strategy corresponding to each machining requirement; coordinating the process sequence of the matched optimized process control strategies according to the principles of roughing before finishing, external before internal, primary before secondary, indexing of symmetrical features, and postponing of easily deformable features, and inserting measurement feedback and parameter compensation logic between processes to establish a final executable machining strategy sequence; and controlling the CNC machine tool to execute each process sequentially according to the executable machining strategy sequence. This application solves the technical problem in the prior art where the machining accuracy, pass rate, and machining efficiency of irregular surface nut parts cannot be simultaneously achieved.

Description

Technical Field

[0001] This invention relates to the field of machine tool processing, and more specifically to a machine tool processing optimization method and system based on multi-process coordination. Background Technology

[0002] In the field of machining, non-standard irregular-shaped nut parts, as connecting and locking functional components in equipment, directly determine the assembly accuracy and operational reliability of the entire machine through their machining accuracy. However, existing CNC machine tools for machining such irregular-shaped nut parts mostly focus on optimizing cutting parameters for a single process or improving machining processes for a single feature, lacking coordination and control between multiple processes. In actual production, there are common problems such as unreasonable process layout logic and improper connection between roughing and finishing processes, leading to the accumulation of cutting stress and machining deformation of parts. At the same time, machining errors generated in previous processes are easily accumulated and transmitted to downstream processes, making it impossible to simultaneously meet the requirements of irregular surface forming accuracy, thread connection accuracy, and overall form and position tolerance of parts. Ultimately, this results in a low pass rate and poor machining efficiency for such irregular-shaped nut parts, making it difficult to meet the demand for high-precision, high-stability, and high-efficiency batch processing of these parts. Summary of the Invention

[0003] This application provides a machine tool processing optimization method and system based on multi-process coordination, aiming to solve the technical problem in the existing technology that the machining accuracy, pass rate and processing efficiency of irregular surface nut parts cannot be simultaneously achieved.

[0004] In view of the above problems, this application provides a machine tool processing optimization method and system based on multi-process coordination.

[0005] The first aspect disclosed in this application provides a machine tool machining optimization method based on multi-process coordination, the method comprising:

[0006] Based on the irregular geometric features of the nut part, the structural machining requirements are analyzed, including the requirements for rough and finish turning of the outer cylindrical surface and end face, the requirements for machining the internal thread bottom hole and chamfer, the requirements for machining the internal thread, the requirements for machining the hexagonal symmetrical surface, and the requirements for machining the flange irregular bevel. These structural machining requirements are matched with various pre-set optimized process control strategies to determine the optimized process control strategy corresponding to each machining requirement. The matched optimized process control strategies are then coordinated according to the principles of roughing before finishing, external before internal, primary before secondary, indexing of symmetrical features, and postponing of easily deformable features. Measurement feedback and parameter compensation logic between processes are inserted to establish the final executable machining strategy sequence. The CNC machine tool is then controlled to execute each process sequentially according to the executable machining strategy sequence.

[0007] Another aspect of this application discloses a machine tool machining optimization system based on multi-process coordination, the system comprising:

[0008] The analysis module is used to analyze the structural machining requirements based on the irregular geometric features of the nut part, including the requirements for rough and finish turning of the outer cylindrical surface and end face, the requirements for machining the internal thread bottom hole and chamfer, the requirements for machining the internal thread, the requirements for machining the hexagonal symmetrical surface, and the requirements for machining the flange irregular bevel. The matching module is used to match the structural machining requirements with a variety of preset optimized process control strategies to determine the optimized process control strategy corresponding to each machining requirement. The coordination module is used to coordinate the process sequence of the matched optimized process control strategies according to the principles of roughing before finishing, external before internal, primary before secondary, indexing of symmetrical features, and postponing of easily deformable features, and inserts measurement feedback and parameter compensation logic between processes to establish the final executable machining strategy sequence. The execution module is used to control the CNC machine tool to execute each process sequentially according to the executable machining strategy sequence.

[0009] One or more technical solutions provided in this application have at least the following technical effects or advantages:

[0010] By analyzing the irregular surface geometric features of nut parts, structured structural processing requirements are obtained. Then, corresponding optimized process control strategies are matched for each processing requirement. Following the principles of roughing before finishing, external before internal, primary before secondary, symmetrical feature indexing, and postponing easily deformable features, the process sequence is coordinated. At the same time, measurement feedback and parameter compensation logic between processes are inserted. Finally, an executable processing strategy sequence is established and the CNC machine tool is controlled to complete the entire process. This technical solution realizes the collaborative optimization of multiple processes in the entire nut part processing process, effectively reduces part deformation and internal stress accumulation during the cutting process, and prevents the cumulative transmission of processing errors from previous processes to downstream processes. It achieves a synergistic unity of high precision, high pass rate, and high processing efficiency.

[0011] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0012] Figure 1 A flowchart illustrating a machine tool processing optimization method based on multi-process coordination is provided for embodiments of this application;

[0013] Figure 2 A schematic diagram of a machine tool processing optimization system based on multi-process coordination is provided for the embodiments of this application.

[0014] Explanation of reference numerals in the attached diagram: Parsing module 11, Matching module 12, Coordination module 13, Execution module 14. Detailed Implementation

[0015] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided below.

[0016] The overall concept of the technical solution provided in this application is as follows:

[0017] This application provides a machine tool machining optimization method and system based on multi-process coordination. By analyzing the structured machining requirements based on the irregular surface geometric features of nut parts, a dedicated optimized process control strategy is precisely matched for each machining requirement. Then, following the principles of roughing before finishing, external before internal, main before secondary, symmetrical feature indexing, and post-deformable features, the multi-process sequence is coordinated. At the same time, full-process online measurement feedback, parameter compensation logic, stress relief links, and auxiliary chip removal instructions are embedded between processes to construct a complete executable machining strategy sequence and drive the CNC machine tool to execute it sequentially. Finally, the collaborative optimization of the entire process of machining irregular surface nut parts is achieved, meeting the high-precision, high-stability, and high-efficiency batch machining requirements of irregular structure nut parts.

[0018] After introducing the basic principles of this application, various non-limiting embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0019] Example 1, as Figure 1 As shown in the embodiments of this application, a machine tool processing optimization method based on multi-process coordination is provided, the method comprising:

[0020] S100: Based on the irregular geometric features of the nut parts, analyze the structural machining requirements, including the rough and finish turning requirements of the outer cylindrical surface and end face, the machining requirements of the internal thread bottom hole and chamfer, the machining requirements of the internal thread, the machining requirements of the hexagonal symmetrical surface, and the machining requirements of the flange irregular bevel.

[0021] Specifically, the analysis first focuses on the irregular surface geometric features of the target nut part. Irregular surface geometric features refer to the set of geometric shapes of the nut part that distinguish it from the standard rotating nut, including irregular contours and asymmetrical machining elements. These include non-standard forming structures such as flange irregular bevels and hexagonal symmetrical surfaces. The geometric topology traversal algorithm identifies all the feature elements to be machined on the nut part. According to the feature classification rules commonly used in the field of machining, the identified features are divided into five categories: rotating body features, hole features, thread features, planar features, and freeform surface features. Among them, rotating body features correspond to the subsequent machining objects of the outer cylindrical surface and end face, hole features correspond to the machining objects of the internal thread bottom hole and chamfer, thread features correspond to the machining objects of the internal thread, planar features correspond to the machining objects of the hexagonal symmetrical surface, and freeform surface features correspond to the machining objects of the flange irregular bevel.

[0022] After classification, for each category of machining features, the corresponding core geometric parameters and form and position accuracy requirements are extracted one by one. Geometric parameters refer to the quantitative indicators that characterize the boundary of feature dimensions, including core dimension values ​​such as nominal outer diameter, inner hole depth, nominal thread diameter and pitch, inclined plane angle, and distance between opposite sides of the hexagon. Form and position accuracy requirements are the shape tolerance and position tolerance thresholds that the corresponding features must meet, including roundness, cylindricity, parallelism, symmetry, cumulative error of thread pitch, and inclined plane angle deviation, which determine the final machining qualification of the part.

[0023] Subsequently, considering the base material properties of the nut part, including material hardness, machinability, thermal deformation coefficient, and the initial blank state, including total blank allowance, datum surface forming state, and clamping and positioning datum position, a corresponding machining process type and machining level requirement are matched for each type of machining feature. This generates a complete list of machining requirements, including rough and finish turning requirements for external cylindrical surfaces and end faces, internal thread bottom holes and chamfering requirements, internal thread machining requirements, hexagonal symmetrical surface machining requirements, and flange irregular bevel machining requirements. The rough and finish turning requirements for external cylindrical surfaces and end faces refer to... The rotating features are designed with two levels of machining requirements: a roughing process for rapid removal of large allowances and a finishing process to ensure the final dimensions and positional accuracy. The internal thread bottom hole and chamfer machining requirements refer to the pre-machining requirements for machining the pre-formed base hole and end guide chamfer for the internal thread. The internal thread machining requirements refer to the forming machining requirements to ensure the thread connection accuracy and meshing performance. The hexagonal symmetrical surface machining requirements refer to the indexing symmetrical plane machining requirements to ensure the locking function of the nut installation. The flange irregular bevel machining requirements refer to the irregular contour surface forming machining requirements to meet the non-standard installation fit.

[0024] Finally, according to the preset sorting rules of prioritizing baseline features, prioritizing the removal of large allowances, prioritizing high-precision features, and placing easily deformable features last, the generated processing requirement list is sorted by priority, and structured processing requirements that can be directly used for subsequent optimization of process control strategy matching are output.

[0025] S200: Match the structural processing requirements with a variety of preset optimized process control strategies to determine the optimized process control strategy corresponding to each processing requirement.

[0026] Specifically, the process begins with structural machining requirements as input. These requirements, after feature recognition, classification, parameter extraction, and priority ranking, output five core machining categories: rough and finish turning of the outer cylindrical surface and end face of nut parts, machining of internal threaded bottom holes and chamfers, internal thread machining, machining of hexagonal symmetrical surfaces, and machining of flange irregular bevels. Each category has a clearly defined set of standardized machining requirements, including feature geometric parameters, geometrical accuracy thresholds, part material compatibility requirements, and blank allowance status. This is supported by a pre-defined, optimized process control strategy library—a set of standardized cutting control schemes customized for different machining feature types, cutting conditions, and accuracy levels, verified through cutting processes. Specifically, this includes wide cutting edges for outer diameters, steps, and end faces. The system comprises eight major categories: thin chip control strategy, short hole / shallow groove intermittent feed and chip removal control strategy, deep hole segmented retraction and emulsion lubrication strategy, narrow groove / precision step extremely slow feed and elastic deformation elimination strategy, thread machining spindle and feed synchronization strategy, circumferential symmetrical feature indexing micro-cutting and real-time compensation strategy, irregular surface layer-by-layer milling and tool radius compensation strategy, and auxiliary chip removal and stress relief strategy. Each strategy clearly defines the full-process execution specifications for tool selection rules, cutting parameter ranges, feed motion modes, chip removal and lubrication schemes, and error pre-control logic. As a matching benchmark, a one-to-one correspondence matching rule is established between machining feature type, accuracy level, machining requirements, and control strategy. The matching is carried out item by item according to the priority-sorted list of machining requirements.

[0027] For the rough and finish turning requirements of external cylindrical surfaces and end faces, a corresponding wide-edge thin-chip control strategy is matched for external diameters / steps / end faces. The wide-edge thin-chip control strategy refers to a special turning control scheme that uses a wide-edge cutting tool, sets the tool tip below the center of the workpiece, and sets an appropriate principal cutting edge angle to form an extremely thin chip layer, thereby reducing cutting resistance and workpiece deformation. At the same time, it clarifies two levels of execution rules: using rapid cutting in the rough turning stage to achieve efficient removal of large allowances, and using micro-feed in the finish turning stage to ensure the final dimensions and positional accuracy.

[0028] For the machining requirements of internal thread bottom holes and chamfering, a corresponding short hole / shallow groove intermittent feed and chip removal control strategy is matched. The intermittent feed and chip removal control strategy refers to a drilling control scheme that uses a drill bit with chip removal grooves to achieve reliable chip breaking and smooth chip removal through intermittent cutting feed, while continuously spraying cutting fluid throughout the machining process to achieve sufficient cooling and lubrication. At the same time, the execution rule of using a forming tool to form the chamfering process in one step is clearly defined.

[0029] To meet the needs of internal thread machining, a corresponding thread machining spindle and feed synchronization strategy is matched. The spindle and feed synchronization strategy refers to the use of a fully closed-loop control of the CNC system to maintain a strict linear synchronization relationship between the spindle speed and the feed rate. The execution rules are clearly defined, including the use of carbide thread cutting tools, multiple passes with decreasing depth of cut in each pass, and the final pass being a no-reserve finishing pass.

[0030] To address the machining requirements of hexagonal symmetrical surfaces, a corresponding indexing micro-cutting and real-time compensation strategy for circumferential symmetry features is employed. This strategy involves using the machine tool's C-axis as the rotation center and achieving high-precision indexing and positioning at equal angles based on the number of hexagonal faces. Micro-cutting significantly reduces machining stress and part deformation. Simultaneously, a dedicated symmetrical plane milling control scheme is implemented for online detection and automatic compensation of form and position errors during machining. This scheme specifies that parallelism is checked online after machining every two planes, and a closed-loop execution rule automatically corrects the tool radius compensation value if the parallelism deviation exceeds a preset threshold.

[0031] To address the machining requirements of flange irregular inclined surfaces, a corresponding irregular surface layer-by-layer milling and tool radius compensation strategy is matched. The layer-by-layer milling and tool radius compensation strategy here refers to using a ball end mill to perform micron-level layer-by-layer milling along the inclined surface contour, and enabling tool radius compensation throughout the process to eliminate the impact of tool wear on contour accuracy. At the same time, a dedicated freeform surface milling control scheme is provided for contour angle detection and dynamic toolpath correction during the machining process. The execution rules specify that after each preset number of milling layers, the actual angle of the inclined surface is detected. If the deviation between the actual angle and the theoretical angle exceeds a preset threshold, the subsequent toolpath trajectory is recalculated and the tool posture is adjusted.

[0032] After matching all five categories of processing requirements with their corresponding optimized process control strategies, the optimized process control strategy corresponding to each processing requirement, which solidifies the execution rules of the entire process, is output, thus completing the entire matching process.

[0033] S300: The matched optimized process control strategies are coordinated according to the principles of roughing before finishing, external before internal, primary before secondary, symmetrical feature indexing processing, and easy-to-deform features being placed later. Measurement feedback and parameter compensation logic between processes are inserted to establish the final executable processing strategy sequence.

[0034] Specifically, the initial input unit is based on the optimized process control strategies for five major categories of machining requirements corresponding to the matched nut parts: rough and finish turning of the outer cylindrical surface and end face, machining of the internal thread bottom hole and chamfer, internal thread machining, machining of the hexagonal symmetrical surface, and machining of the flange irregular bevel. Five principles for coordinating the process sequence are clarified, and the initial process sequence is constructed. "Rough before finish" means prioritizing roughing processes that remove large allowances, followed by finishing processes that ensure final accuracy. "Outer before inner" means prioritizing machining processes for external features such as the outer contour and outer cylindrical surface, followed by machining processes for internal features such as inner holes and internal threads. A stable external machining surface serves as the clamping and positioning datum to ensure the machining positioning accuracy of internal features. "Primary before secondary" means... The strategy prioritizes the machining of the main features that determine the core connection and installation functions of the part, followed by the machining of auxiliary and secondary features. Symmetrical feature indexing machining refers to the concentrated process mode of continuous indexing and paired machining of circumferential symmetrical features such as hexagonal shapes. Deformable features are placed later, which means that the machining of features that are prone to stress deformation after cutting, such as flanges and irregular bevels, is arranged at the end of the process. Based on the above principles, the strategy of prioritizing the roughing and finishing of the outer cylindrical surface and end face is adopted. First, the datum surface of the part is established and the large allowance is quickly removed to establish a unified machining and measurement datum for the part. Then, the internal thread bottom hole and chamfering machining and internal thread machining processes are arranged in sequence according to the principle of outside to inside, so as to complete the pre-forming and final machining of the core internal thread connection feature.

[0035] Subsequently, following the principle of indexing machining for symmetrical features, the indexing milling process for the hexagonal symmetrical surface is arranged in a concentrated manner to ensure the indexing accuracy and geometric tolerances of the symmetrical features. Finally, according to the principle of placing easily deformable features later, the layer-by-layer milling process for the flange's irregular bevel is arranged at the end of the entire process, thus generating a logically coherent initial process sequence. Based on this, online measurement points are inserted between adjacent key processes in the initial process sequence. These are online measurement nodes for dimensions and geometric tolerances set after the key features are machined and before the next process starts. Specifically, this covers the measurement of diameter and roundness after the outer circle is precision turned, and the hexagonal symmetrical surface is milled later. The system measures symmetry and parallelism after rough milling of corner faces, pitch error after thread machining, and angle during inclined milling to achieve real-time verification of machining quality for each key process. Simultaneously, it embeds corresponding parameter compensation logic for each online measurement point, which is a closed-loop control rule that automatically corrects subsequent machining parameters based on measured accuracy data. This includes four main categories: tool radius compensation, adaptive feed rate adjustment, cooling strategy adjustment, and tool posture reset. If the measured data exceeds the preset accuracy threshold, the system will automatically trigger the corresponding compensation logic to correct the machining parameters of subsequent processes in real time, eliminating machining errors generated by previous processes.

[0036] Subsequently, before the easily deformable feature process, a stress-relief idle run is forcibly inserted. The stress-relief idle run refers to the spindle idling at a set speed for a preset time to fully release the cutting stress accumulated inside the part in the previous roughing process, thereby reducing the form and position deviation after the easily deformable feature is processed from the source. At the same time, after each milling process and in places where chips are prone to accumulate, such as internal hole and thread machining, auxiliary chip removal instructions are forcibly inserted. These instructions include M89 code and cutting fluid pulse injection to prevent residual chips from scratching the machined precision surface and affecting the clamping and positioning accuracy of subsequent processes. Finally, all process modules that have been scientifically sorted, have inserted online measurement points throughout the process, have embedded closed-loop parameter compensation logic, and have supplemented stress relief and auxiliary chip removal instructions are logically integrated and adapted to machine tool codes to form a set of conflict-free, directly recognizable and continuously executed final executable machining strategy sequence.

[0037] S400: Control the CNC machine tool to execute each process sequentially according to the executable machining strategy sequence.

[0038] Specifically, the first step is to use the final executable machining strategy sequence as the execution input. This involves completing the pre-initialization and compliance verification of the CNC machine tool and the machining process. This includes fully loading the strategy sequence of the CNC system, accurately calibrating the machining coordinate system, pre-setting and verifying the tool parameters of all tools required for the process, such as wide-blade turning tools, carbide thread cutters, and ball end mills in the tool magazine, zeroing the accuracy of the spindle and each feed axis, verifying the pressure and flow of the cooling and lubrication system, and calibrating the accuracy of the online probe. This ensures that the machine tool hardware and system status are fully matched to the execution requirements of the strategy sequence. Simultaneously, the precise clamping and positioning of the nut blank is completed. Using the preset outer circle reference surface in the strategy sequence as the clamping and positioning reference, radial and axial alignment and clamping force verification are completed.

[0039] After initialization and verification, the CNC system strictly follows the process-level sequence execution rules to initiate the machining actions of each process sequentially. The execution rules mean strictly adhering to the preset sequence of processes according to the executable machining strategy. The system cannot jump to the next process until all actions of a single process are completed and the preset node verification rules are passed. When performing rough and finish turning of the external cylindrical surface and end face, the system strictly calls the preset parameters of the matched wide-blade thin-chip control strategy, precisely controls the tool tip installation height and principal cutting edge angle setting, and executes the rapid cutting and large-mass removal in the roughing stage and the micro-feed high-precision forming actions in the finish turning stage, simultaneously initiating the corresponding cooling and lubrication commands. When performing the internal thread bottom hole and chamfering machining processes, the system strictly... The system employs an intermittent feed and chip removal control strategy, controlling the drill bit with chip grooves to perform intermittent cutting feed. Throughout the machining process, cutting fluid is continuously sprayed for cooling and chip removal. The chamfering process automatically calls the forming tool to complete the forming process in one pass. When performing internal thread machining, the system automatically triggers the spindle and feed synchronization control logic. This involves using a fully closed-loop servo control system to maintain a strict linear synchronization between the spindle rotation speed and the Z-axis feed speed, fundamentally ensuring the core control rules for thread pitch machining accuracy. The system strictly follows the preset rules of multiple passes, progressively decreasing depth of cut, and a final pass with no allowance for finishing to complete the thread forming process. When performing hexagonal symmetrical surface machining, the system strictly adheres to the circumferential symmetry feature indexing micro-... The cutting control strategy uses the machine tool's C-axis as the rotation center to complete high-precision indexing and positioning at equal angles according to the number of hexagonal faces. After each indexing, a micro-cutting method is used to complete single-plane machining. After machining two relative planes, the system automatically triggers the preset online measurement points in the strategy sequence. That is, when the process reaches the preset node, the system automatically pauses the cutting process and calls the machine tool's online probe to complete the dimensional and geometrical accuracy detection of the corresponding features. The standardized verification node compares the measured data with the theoretical threshold to complete the online parallelism detection. If the measured parallelism deviation exceeds the preset threshold, the system automatically executes the embedded parameter compensation logic, that is, it automatically corrects the closed-loop control rules of subsequent machining parameters based on the measurement results and automatically completes tool radius compensation. After the value is corrected, the subsequent indexing and machining operations continue. Before performing the flange irregular inclined surface machining process, the system strictly executes the stress relief idle run phase that is forcibly inserted in the strategy sequence, controlling the spindle to idle at the set speed for a preset time to fully release the cutting stress accumulated inside the part in the previous roughing process. Then, the irregular surface layer-by-layer milling and tool radius compensation strategy is started, controlling the ball end mill to complete the micron-level layer-by-layer milling along the inclined surface contour. Tool radius compensation is enabled throughout the process to eliminate the contour deviation caused by tool wear. After each preset number of milling layers, the inclined surface angle is automatically triggered for online measurement. If the deviation between the measured angle and the theoretical angle exceeds the preset threshold, the system automatically recalculates the subsequent tool path and adjusts the tool posture before continuing the subsequent milling process.

[0040] During the entire process, after each milling operation, internal hole and thread machining operation where chips tend to accumulate, the system automatically executes the preset auxiliary chip removal commands in the strategy sequence, including M89 code triggering and cutting fluid pulse injection, to thoroughly clean the residual chips in the machining area. At the same time, the CNC system collects the entire process operation parameters in real time, such as spindle load, feed axis position accuracy, tool wear status, and cutting fluid pressure, and compares them with the preset safety thresholds in the strategy sequence. If an abnormal state occurs, it immediately executes pause, alarm, or preset adaptive adjustment actions to ensure the safety and stability of the machining process. After all the operations in the strategy sequence are completed, the system automatically triggers the online measurement for final inspection of the finished product, completes the full dimensional and geometric tolerance verification of all machining features of the nut part, and confirms that all parameters meet the preset machining requirements. After confirming that all parameters meet the preset machining requirements, the system controls the machine tool to complete the finishing actions such as spindle stop, cooling system shutdown, and worktable return to position, completing the entire process machining of the nut part.

[0041] Furthermore, in the method provided in the application embodiments, the preset multiple optimized process control strategies include: wide-edge thin-chip control strategy for outer diameter / step / end face, intermittent feed and chip removal control strategy for short hole / shallow groove, segmented retraction and emulsion lubrication strategy for deep hole, extremely slow feed and elastic deformation elimination strategy for narrow groove / precision step, synchronous strategy for thread machining spindle and feed, indexing micro-cutting and real-time compensation strategy for circumferential symmetry features, layer-by-layer milling of irregular surfaces and tool radius compensation strategy, and auxiliary chip removal and stress relief strategy.

[0042] Specifically, the first step is to construct eight categories of optimized process control strategies covering the entire machining process. Each strategy has completed the full-process solidification and encapsulation of tool selection rules, cutting parameter ranges, feed motion control logic, chip removal and lubrication schemes, and error pre-control and compensation mechanisms. Among them, the wide-edge thin-chip control strategy for outer diameter / step / end face refers to the turning control scheme for machining rotating features such as the outer cylindrical surface, step surface, and end face of nuts. It uses wide-edge forming inserts as machining tools, sets the tool tip installation position to be 0.1-0.2mm lower than the workpiece rotation center, and sets a principal cutting edge angle of 90°-95° ​​to form an extremely thin chip layer with uniform thickness during tool cutting, which greatly reduces cutting resistance and radial cutting deformation of the workpiece. At the same time, it is clearly defined that a high linear speed and large feed rate fast cutting mode is used in the roughing stage to achieve efficient removal of large blank allowances, and a micron-level micro feed and constant linear speed cutting mode is used in the finishing stage to ensure high-precision forming of outer diameter, end face flatness, and step dimensions.

[0043] The short hole / shallow groove intermittent feed and chip removal control strategy refers to the drilling and turning control scheme for machining short-stroke, closed chip space features such as the bottom hole of the nut internal thread, end chamfer, and shallow groove on the end face. Intermittent feed refers to the periodic chip-breaking feed mode of feed-pause-retract during the tool feed process. It uses a special high-speed steel or carbide drill bit with a spiral chip removal groove, and sets the intermittent cutting parameters such that the depth of feed per pass does not exceed 0.5 times the drill bit diameter. After each feed is completed, a short retraction action is performed to smoothly remove the chips in the hole. At the same time, high-pressure emulsion cutting fluid is continuously sprayed throughout the machining process. For chamfering, a forming chamfering tool is used to complete the forming in one pass.

[0044] The deep hole segmented retraction and emulsion lubrication strategy refers to a drilling control scheme for machining deep holes with an aspect ratio greater than 3 in nut parts. Segmented retraction means dividing the total machining depth of the deep hole into multiple equidistant segments. After each segment is completed, the tool is completely withdrawn from the hole to complete chip removal and cooling. The single-segment machining depth is set according to the aspect ratio of the deep hole. The larger the aspect ratio, the smaller the single-segment depth. After each single-segment drilling is completed, the tool is fully retracted to the outside of the hole. At the same time, an internally cooled drill bit is used, and high-pressure emulsion is continuously sprayed onto the cutting edge through the internal oil passage of the drill bit.

[0045] The strategy of extremely slow feed and elastic deformation elimination for narrow grooves / precision steps refers to the turning control scheme for machining narrow grooves and high-precision steps such as sealing grooves and positioning steps of nut parts. Extremely slow feed means that the feed rate is set to 1 / 3 to 1 / 5 of the conventional finishing feed rate, and at the same time, it is combined with a low depth of cut machining mode. It uses a narrow groove forming tool with a sharp cutting edge or a precision step turning tool, sets a single cutting depth in the micrometer level, and combines it with an extremely slow constant feed rate. In addition, after the finishing pass is completed, an additional finishing pass with no depth of cut is added.

[0046] The spindle and feed synchronization strategy for thread machining refers to a thread turning control scheme for machining the internal thread features of nuts. Spindle and feed synchronization means that the spindle rotation speed and Z-axis feed speed are kept in strict linear synchronization through the full closed-loop servo control of the CNC system. That is, for every revolution of the spindle, the Z-axis feed is strictly equal to the nominal pitch of the thread. High-wear-resistant carbide thread forming tools are used, and the spindle-feed synchronization parameters are set to be strictly matched with the thread pitch. The machining mode of multiple passes and progressively decreasing depth of cut is adopted. The depth of cut is the largest on the first pass, and the depth of cut decreases in subsequent passes. The last pass uses a zero-carry-off finishing pass to eliminate machining burrs and deformation on the thread tooth surface.

[0047] The circumferential symmetry feature indexing micro-cutting and real-time compensation strategy refers to a milling control scheme for machining symmetrical features such as the hexagonal symmetry plane of a nut that are evenly distributed around its circumference. Indexing micro-cutting refers to using the C-axis of the machine tool as the rotation center to complete high-precision indexing and positioning at equal angles according to the number of symmetrical features. At the same time, it adopts a micro-cutting machining mode with a single cutting depth not exceeding 0.05mm. A flat-bottomed end mill is used, with the center of rotation of the part as the origin of the polar coordinates. The C-axis indexing and positioning is completed according to the 6 equally divided angles of the hexagonal face. After each indexing, the milling of the corresponding single plane is completed. After each pair of opposite planes is machined, the online probe of the machine tool is automatically called to complete the parallelism and symmetry detection of the two planes. If the measured deviation exceeds the preset accuracy threshold, the system automatically corrects the tool radius compensation value for subsequent machining.

[0048] The layer-by-layer milling and tool radius compensation strategy for irregular free-form surfaces such as nut and flange irregular inclined surfaces refers to a milling control scheme. Layer-by-layer milling means dividing the total machining allowance of the irregular inclined surface into multiple micron-level machining layers along the contour normal. Each layer is milled along the contour line of the inclined surface, using a ball end mill as the machining tool. The depth of cut is set to 0.01-0.03 mm per layer. The tool radius compensation function of the machine tool CNC system is enabled throughout the process to compensate for the contour dimension deviation caused by tool edge wear in real time. After each preset number of layers is milled, the online probe is automatically called to detect the actual inclination angle and contour dimension of the inclined surface. If the deviation between the measured value and the theoretical value exceeds the preset threshold, the system automatically recalculates the tool path trajectory for subsequent machining and adjusts the tool posture.

[0049] The auxiliary chip removal and stress relief strategy refers to an auxiliary control scheme for chip accumulation and cutting stress accumulation problems in the entire machining process. After each milling operation, internal drilling, threading and other operations where chips are prone to accumulate, the M89 auxiliary chip removal code and high-pressure cutting fluid pulse injection command are automatically triggered. At the same time, before the machining operations with easily deformable features, a stress relief idle run is forcibly inserted, that is, the spindle is controlled to idle at a set low speed for a preset time, so that the workpiece can complete the natural release of internal stress in the clamping state.

[0050] Furthermore, in the method provided in the application embodiment, the structural processing requirements are analyzed based on the irregular surface geometric features of the nut part, including: traversing and identifying all processing features in the nut part according to the irregular surface geometric features, classifying them according to feature type, including features of revolution, hole features, thread features, planar features, and freeform surface features; extracting geometric parameters and accuracy requirements for each type of processing feature; generating a corresponding processing requirement list based on the geometric parameters and accuracy requirements, combined with the nut material and blank state; prioritizing the processing requirement list according to the rules of prioritizing datum features, prioritizing large allowance removal, prioritizing high precision features, and postponing easily deformable features, and outputting structured structural processing requirements.

[0051] Specifically, the unique geometric features of the nut part being machined are the sole analytical object. These unique geometric features are the set of geometric shapes that distinguish the nut from a standard rotating nut, including irregular contours and asymmetrical machining elements. These include non-standard forming structures such as flange bevels and hexagonal symmetrical surfaces. These are the control objects for the entire part machining process. A three-dimensional geometric topology traversal algorithm is used to perform a thorough scan of the nut part's digital model, completely identifying all machining features that require material removal to achieve the desired shape. Then, the feature-forming principles commonly used in the machining field are applied. The rules for adaptability to the process and technology classify all identified machining features into five categories. Among them, the features of rotation refer to the features such as the outer cylindrical surface, stepped surface, front and rear end faces formed by rotating around the central axis of the part. These are the reference carriers for part clamping, positioning and machining measurement. The features of holes refer to the internal cavity features such as the internal thread bottom hole, positioning through hole / blind hole, etc. The features of threads refer to the internal thread tooth profile features that realize the core connection function of the nut. The features of planes refer to the hexagonal symmetrical plane features that realize the locking function of the nut. The features of freeform surfaces refer to the non-standard forming features such as irregular irregular inclined surfaces and variable curvature profile surfaces of the flange.

[0052] After completing the classification and aggregation of all machining features, for each category of classified machining features, the corresponding geometric parameters and accuracy requirements are precisely extracted one by one. Geometric parameters refer to the set of quantitative values ​​that characterize the feature's dimensional boundaries and spatial position. Specifically, they include core dimensional data that determine the feature's forming shape, such as the nominal diameter and axial length of the outer circle, the inner diameter and depth of the hole, the nominal diameter and pitch of the thread and the tooth profile angle, the distance between the edges of the hexagonal face and the indexing angle, and the inclination angle and contour curvature radius of the irregular inclined surface. Accuracy requirements refer to the set of dimensional tolerances and geometric tolerance thresholds that the corresponding feature must meet to determine the final qualification of the part. These include the feature's dimensional deviations, roundness, cylindricity, flatness and other shape tolerances, as well as position tolerances such as coaxiality, parallelism, symmetry, position and other positional tolerances. They also include accuracy indicators such as the cumulative error of the thread pitch and the deviation of the tooth profile half angle.

[0053] After extracting all parameters and accuracy requirements, the material properties and blank condition of the nut part are considered. Material properties refer to the core material parameters affecting the machining process, such as the machinability, hardness, thermal deformation coefficient, and stress release characteristics of the nut base material. Blank condition refers to the initial shape of the part blank, i.e., bar stock / forging / casting, total machining allowance, prefabricated datum surface condition, clamping and positioning reserved structure, etc. For each extracted parameter machining feature, the corresponding machining process type, machining level, and allowance allocation scheme are matched to generate a complete machining requirement list covering all elements of rough and finish turning of external cylindrical surfaces and end faces, internal thread bottom hole and chamfering, internal thread machining, hexagonal symmetrical surface machining, and flange irregular bevel machining. Each requirement in this list is bound to the corresponding machining feature, clearly indicating the feature type, geometric parameters, accuracy requirements, and suitable machining method.

[0054] Finally, the processing requirements list is sorted hierarchically according to four priority sorting rules. The datum feature priority rule puts the machining requirements of rotating features, outer cylindrical surfaces, and end faces, which serve as the datum for clamping, positioning, and measuring the entire part, at the forefront of the sequence. The large allowance removal priority rule puts the machining requirements of roughing and blank with large allowance removal at the forefront, prioritizing the rapid removal of most of the allowance. The high precision feature priority rule puts the core functional features with high tolerance levels and strict precision requirements, such as internal threads and datum outer circles, in positions with more stable stress environments in the process chain. The easily deformable feature placement rule puts the machining requirements of thin-walled and irregular features, such as flanges and irregular bevels, which are prone to stress rebound and clamping deformation after machining, at the end of the sequence. After completing the priority sorting, the final output is a structured machining requirement with hierarchical priority, binding all feature parameters and precision requirements, and clearly defining the machining direction.

[0055] Furthermore, in the method provided in the application embodiment, the optimized process control strategy corresponding to each machining requirement is determined, including: for the rough and finish turning requirements of the outer cylindrical surface and end face, the matched optimized process control strategy is to use a wide-bladed tool, set the tool tip at a position lower than the center of the workpiece, and set the main cutting edge angle to form a thin chip layer; rapid cutting is used during rough turning, and micro-feed is used during finish turning.

[0056] Specifically, the first step involves the roughing and finishing requirements for the outer cylindrical surface and end face. This is defined after feature classification, geometric parameter extraction, and accuracy requirements extraction, and represents two levels of machining requirements for the rotating features of the nut part. Roughing aims to quickly remove most of the machining allowance from the outer diameter and end face of the blank. Finishing, on the other hand, focuses on ensuring the core datum geometric tolerances such as outer diameter tolerance, roundness, cylindricity, end face flatness, and axial dimensional accuracy. It also incorporates standardized machining requirements for boundary conditions such as the machinability of the nut base material, total blank allowance, and accuracy thresholds. Using these as inputs, a pre-defined wide-edge thin-chip control strategy for the outer diameter / step / end face is used as the matching benchmark for full-element matching. The control logic of this strategy is defined as wide-edge thin-chip control. Wide-edge thin-chip refers to the use of wide-edge forming tools, appropriate tool tip mounting positions, and principal cutting edge angle settings to create extremely thin chips with uniform thickness, significantly thinner than those produced by conventional turning. The turning control principle, which significantly reduces cutting resistance, cutting heat, and radial cutting deformation of the workpiece, involves the precise setting of tool selection and installation posture in the first step. Wide-bladed carbide inserts are used as the machining tool, with the cutting edge width covering the stepped area where the outer circle and end face meet, enabling the forming of the joint to be completed in a single pass. Simultaneously, the tool tip installation position is strictly set, placing the tool tip 0.1mm-0.2mm below the workpiece's rotation center. This installation method significantly reduces the radial cutting force during cutting by changing the actual working rake angle of the tool, suppressing radial deflection and cutting vibration during workpiece machining. A principal cutting edge angle of 90°-95° ​​is simultaneously set; the principal cutting edge angle is the angle between the tool's main cutting edge and the workpiece's feed direction. This angle range allows the cutting force to be concentrated more along the workpiece's axial direction, further reducing the radial cutting force and forming a stable thin chip layer in conjunction with the wide-bladed insert.

[0057] The second step involves setting differentiated parameters for the roughing and finishing cutting modes to fully match the machining requirements of both stages. For roughing, a rapid cutting mode is used, employing a combination of high spindle speed, large feed rate, and large depth of cut. Based on thin chip control, this allows for efficient removal of most of the workpiece's allowance in a single pass, significantly shortening the roughing cycle. Simultaneously, the large allowance removal in a single pass reduces the number of roughing passes, minimizing stress accumulation in the workpiece from multiple cuts. For finishing, a micro-feed finishing mode is used, setting the feed rate to a micrometer-level range of 0.05mm / r-0.1mm / r, combined with a small depth of cut of 0.05mm-0.1mm. Under thin chip control logic, this achieves smoothing of the outer diameter and end face, ensuring the dimensional tolerances, roundness, and cylindricity of the outer diameter, as well as the flatness of the end face and its perpendicularity to the reference axis. This is achieved simultaneously with constant surface speed cutting control to ensure consistent surface roughness across the entire length of the outer diameter.

[0058] The third step is to bind all elements of the strategy and machining requirements together. All control rules, such as tool selection parameters, tool tip installation position, principal cutting edge angle setting value, rough turning rapid cutting parameters, finish turning micro feed parameters, and matching cooling and lubrication requirements, are bound one by one to the rough and finish turning requirements of the outer cylindrical surface and end face of the nut. This forms a standardized turning process control unit that can be directly embedded into the subsequent process sequence and executed directly by the machine tool.

[0059] Furthermore, in the method provided in the application embodiment, the optimized process control strategy corresponding to each processing requirement is determined, including: for the internal thread bottom hole and chamfer processing requirements, the matched optimized process control strategy is to use a drill bit with chip removal grooves, process in an intermittent cutting manner, and continuously spray cutting fluid during the processing; chamfering is done with a forming tool; for the internal thread processing requirements, the matched optimized process control strategy is to use a carbide threading tool and strictly synchronize the spindle speed and feed rate; thread processing adopts a multi-pass method, with the depth of cut decreasing with each pass, and the last pass is a finishing pass.

[0060] Specifically, the first step is to define the machining requirements for the internal thread bottom hole and chamfer, which are clarified after feature classification, geometric parameters, and accuracy requirements extraction. These requirements define the pre-machining requirements for the internal thread forming base hole and the end guide chamfer. This includes standardized machining requirements for the bottom hole diameter tolerance, hole depth, coaxiality with the reference outer circle, chamfer angle and dimensional accuracy, as well as the cutting performance of the nut base material and the state of the pre-made hole in the blank. These standardized machining requirements serve as the first matching input. The matching scheme's pre-set short hole / shallow groove intermittent feed and chip removal control strategy first achieves precise adaptation between the tool and the machining mode. The matching uses a drill bit with chip removal flutes. A drill bit with chip removal flutes refers to a helical chip removal flute made of carbide or high-speed steel that is adapted to the length-to-diameter ratio of the internal thread bottom hole. The flute shape has been optimized. The design enables stable chip breaking and smooth chip removal. It also incorporates an intermittent cutting mode as the feed control logic, where the depth of each feed is set to no more than 0.5 times the drill bit diameter. After each feed stroke, a brief retraction action is performed to smoothly remove chips generated inside the hole. Simultaneously, continuous cooling and lubrication control with cutting fluid is implemented throughout the bottom hole machining process. This involves continuously spraying high-pressure emulsified cutting fluid onto the drill bit's cutting edge area via the machine tool's cooling system, further enhancing chip removal. For the chamfering stage, a forming tool is used. This forming tool is an integrated chamfering tool that perfectly matches the preset chamfer angle and end dimensions, allowing for the completion of the full contour forming of the chamfer in a single pass.

[0061] Subsequently, based on the internal thread machining requirements—that is, the thread forming machining requirements that are clearly defined after feature classification, geometric parameters, and accuracy requirements are extracted—to achieve the core connection and locking function of the nut, core parameters and accuracy thresholds such as nominal thread diameter, pitch, thread angle, cumulative pitch error, thread half-angle deviation, and thread meshing accuracy, as well as standardized machining requirements for boundary conditions such as the cutting performance of the nut material and the pre-machining state of the bottom hole, are bound as the second matching input. The thread machining spindle and feed synchronization strategy preset in the matching scheme first completes the tool selection and core synchronization control logic setting. Carbide thread cutting tools are used for matching. Carbide thread cutting tools refer to special forming thread turning tools with high cutting edge forming accuracy and excellent wear resistance. At the same time, the core control rule of strict synchronization between spindle speed and feed speed is set. Strict synchronization between spindle and feed means that through the full closed-loop servo control of the machine tool CNC system, the spindle rotation speed and Z-axis feed speed maintain a strict linear synchronization relationship. That is, for each complete rotation of the spindle, the feed amount of the Z-axis is strictly equal to the nominal thread pitch.

[0062] Subsequently, a multi-pass cutting mode was set for the thread forming process, with the depth of cut decreasing with each pass. The final pass was a finishing pass. The multi-pass decreasing depth of cut mode divides the total cutting depth of the thread profile into multiple continuous cutting segments. The first pass uses the maximum cutting depth to remove most of the allowance. The cutting depth of each subsequent pass decreases sequentially. The final pass is set as a finishing pass with no cutting allowance to eliminate machining burrs on the thread profile surface and thread profile deviations caused by the elastic rebound of the workpiece material. This further optimizes the thread profile accuracy and surface roughness. Finally, all tool selection parameters, feed control logic, cutting parameters, cooling and lubrication rules, and synchronization control schemes corresponding to the two processing requirements are bound to the corresponding processing requirements one by one, forming a standardized internal hole and thread processing process control unit that can be directly embedded into the subsequent process sequence and executed directly by the machine tool.

[0063] Furthermore, in the method provided in the application embodiment, determining the optimized process control strategy corresponding to each processing requirement includes: for the processing requirement of a hexagonal symmetrical surface, the matched optimized process control strategy is to use a polar coordinate indexing processing method, with the C-axis as the center and the number of hexagonal faces equally spaced, and to process one plane after each indexing, using a micro-cutting method; after processing every two planes, the parallelism is detected, and if the parallelism deviation exceeds a preset threshold, the tool radius compensation value is automatically corrected; for the processing requirement of a flange irregular inclined surface, the matched optimized process control strategy is to use a ball end mill to mill along the inclined surface contour layer by layer, with each layer having a cutting depth of micrometers, and to enable tool radius compensation; after milling several layers, the actual angle of the inclined surface is detected, and if the deviation between the actual angle and the theoretical angle exceeds a preset threshold, the subsequent toolpath trajectory is recalculated and the tool posture is adjusted.

[0064] Specifically, the first step is to address the machining requirements of the hexagonal symmetrical surface. This involves defining the machining requirements for six circumferentially distributed symmetrical planes that enable the nut installation and locking function, after feature classification, geometric parameter extraction, and accuracy requirements. This is tied to core parameters and accuracy thresholds such as the tolerance of the distance between opposite sides of the hexagon, the indexing accuracy of adjacent surfaces, the parallelism of opposite surfaces, overall symmetry, and the perpendicularity of the plane to the reference rotation axis. Standardized machining requirements for boundary conditions, including the cutting performance of the nut base material, the reference state of the blank's outer circle, and clamping and positioning conditions, serve as the first matching input. The matching scheme's pre-set circumferential symmetrical feature indexing micro-cutting and real-time compensation strategy first completes the precise adaptation of the machining mode and control logic. The matching adopts a polar coordinate indexing machining method. Polar coordinate indexing machining refers to a milling machining mode that uses the machine tool's C-axis (the spindle rotation axis) as the rotation control center and the part's reference rotation axis as the polar coordinate origin, performing high-precision equal-angle indexing positioning according to the number of symmetrical features. In specific execution, the C-axis... The C-axis is indexed at 60° angles, with the axis as the center and the six equally divided hexagonal faces. After each 60° indexing and positioning, the C-axis is locked, and then the corresponding single plane is machined to avoid positioning deviations during the indexing process. At the same time, a micro-cutting mode is adopted as the core cutting control logic. The micro-cutting mode refers to a small-allowance cutting mode that controls the depth of cut of a single pass to within 0.05mm. Subsequently, a closed-loop accuracy compensation logic is embedded to strictly implement the rule of triggering parallelism detection after machining two opposing planes. That is, after each set of milling of opposing planes is completed, the machine tool's online probe is automatically called to complete the actual parallelism detection of the two planes. The measured value is compared with the preset accuracy threshold. If the parallelism deviation exceeds the preset threshold, the system automatically triggers the tool radius compensation value correction action. That is, the tool radius compensation parameters for subsequent machining are automatically calculated and updated based on the measured deviation to offset the dimensional and positional deviations caused by indexing and positioning errors, tool edge wear, and cutting deflection.

[0065] Subsequently, based on the machining requirements of the flange's irregular inclined surface, namely the machining requirements of the irregular variable angle and curvature profile surface of the nut flange area after feature classification, geometric parameter extraction, and accuracy requirements, core parameters and accuracy thresholds such as the theoretical inclination angle of the inclined surface, profile forming accuracy, surface roughness, and positional accuracy of the inclined surface relative to the reference axis were bound. It was also clarified that this feature belongs to a thin-walled irregular structure that is easily deformed by cutting, requiring standardized machining requirements for boundary conditions matching a low-stress machining mode. As the second matching input, the matching scheme's pre-set irregular surface layer-by-layer milling and tool radius compensation strategy first completed the tool selection and core cutting mode adaptation. A ball end mill was used as the machining tool; here, a ball end mill refers to a forming milling cutter with a spherical profile cutting edge. Simultaneously, the core machining logic of layer-by-layer milling along the inclined surface profile was set. Layer-by-layer milling means dividing the total machining allowance of the irregular inclined surface into multiple machining layers of equal thickness along the profile normal. Each layer completes continuous milling along the theoretical profile line of the inclined surface, while strictly controlling the depth of cut of each layer to the micrometer level, i.e., single... The depth of cut for each layer is controlled between 0.01mm and 0.03mm. Tool radius compensation is enabled throughout the machining process. Tool radius compensation refers to the machine tool CNC system automatically offsetting and calculating the tool path based on the actual measured value of the tool radius throughout the entire process, compensating in real time for contour forming errors caused by tool edge wear and tool radius deviation, and continuously ensuring the contour accuracy of the irregular surface during the machining process. Subsequently, a dynamic closed-loop correction logic is embedded to strictly implement the rule of detecting the actual angle of the inclined surface after each preset number of milling layers. That is, after completing 3-5 layers of milling, the machine tool's online probe is automatically called to complete the actual tilt angle detection of multiple points on the inclined surface. The average angle value measured at multiple points is compared with the theoretical angle value. If the deviation between the actual angle and the theoretical angle exceeds the preset threshold, the system automatically triggers the recalculation of the subsequent tool path and the tool posture adjustment action. That is, the theoretical contour of the inclined surface is refitted according to the measured angle deviation, the tool path coordinates of subsequent machining are updated, and the cutting posture and feed angle of the tool are adjusted simultaneously to offset the angle deviation of the previous machining.

[0066] Ultimately, all tool selection parameters, indexing control logic, cutting parameters, closed-loop compensation rules, cooling and lubrication requirements, and other full-process execution specifications corresponding to the two processing requirements are bound to the corresponding processing requirements one by one, forming a standardized irregular feature milling process control unit that can be directly embedded into subsequent process sequences and executed directly by machine tools.

[0067] Furthermore, in the method provided in the application embodiment, establishing the final executable machining strategy sequence includes: sequentially sorting the matched optimized process control strategies according to the principles of roughing before finishing, external before internal, primary before secondary, symmetrical feature indexing machining, and easily deformable features being placed later, to generate an initial process sequence; based on the initial process sequence, inserting online measurement points between adjacent processes, the online measurement points including diameter and roundness measurement after external cylindrical finishing, symmetry and parallelism measurement after hexagonal surface rough milling, pitch error measurement after thread machining, and angle measurement during inclined milling; and according to the actual online measurement points... The measurement results are embedded with parameter compensation logic, which includes: tool radius compensation, feed rate adaptive adjustment, cooling strategy adjustment, and tool posture reset. Before easily deformable characteristic processes, a stress-relief idle run is forcibly inserted, in which the main spindle idles at a set speed for a preset duration. After each milling process and at locations where chips tend to accumulate, auxiliary chip removal commands are forcibly inserted, including M89 code and cutting fluid pulse injection. The process sequence after sorting, inserting measurement points, compensation logic, stress relief process, and chip removal commands is integrated to obtain the final executable machining strategy sequence.

[0068] Specifically, the system first uses the optimized process control strategies for the five core machining requirements of the matched nut part—rough and finish turning of the outer cylindrical surface and end face, machining of the internal thread bottom hole and chamfer, internal thread machining, machining of the hexagonal symmetrical surface, and machining of the flange irregular bevel—as the basic input unit. The process sequence is then ordered according to five principles: roughing before finishing, outer before inner, main before secondary, indexing of symmetrical features, and placing easily deformable features later. Roughing before finishing refers to prioritizing roughing processes that remove large allowances, followed by finishing processes that ensure final dimensional and geometrical accuracy. Outer before inner refers to prioritizing the outer contour of the part. The machining processes for external features such as outer cylindrical surfaces are arranged first, followed by the machining processes for internal features such as inner holes and internal threads. The stable outer surface that has been machined first is used as the unified clamping and positioning reference. The "primary features first, secondary features later" approach means that the machining processes for the main features that determine the core connection and installation function of the nut are arranged first, followed by the machining processes for the auxiliary secondary features. The "symmetric feature indexing machining" approach means that the concentrated process mode of continuous indexing and paired machining is used for symmetrical features such as hexagonal shapes that are evenly distributed around the circumference. The "deformable features later" approach means that the machining processes for thin-walled irregular features such as flange irregular bevels that are prone to stress rebound and clamping deformation after cutting are arranged at the end of the entire process.

[0069] Based on the above principles, the roughing and finishing machining strategies for the outer cylindrical surface and end face are prioritized to establish a unified machining and measurement benchmark for the parts. Then, following the principle of processing from the outside to the inside, the machining strategies for the internal thread bottom hole and chamfering, and the internal thread machining are arranged in sequence to complete the machining of the core connection function features of the nut. Subsequently, according to the principle of indexing machining of symmetrical features, the roughing and finishing milling indexing machining strategies for the symmetrical hexagonal surface are arranged in a concentrated manner. Finally, according to the principle of placing easily deformable features later, the layer-by-layer milling machining strategy for the flange irregular inclined surface is arranged at the end of the entire process, thereby generating an initial process sequence that is logically coherent and conforms to the machining principle.

[0070] Based on this, online measurement points are inserted between adjacent key processes in the initial process sequence. These online measurement points refer to the online detection nodes for dimensions and geometrical accuracy set after the corresponding key features are processed and before the next process starts. These include four main categories of core detection items: diameter and roundness measurement after external cylindrical precision turning, symmetry and parallelism measurement after hexagonal rough milling, pitch error measurement after thread processing, and angle measurement during inclined milling. These are used to verify the part's datum accuracy, identify symmetrical feature indexing errors in advance, ensure the accuracy of core thread functions, and monitor the forming deviation of irregular inclined surfaces during the process, thereby achieving real-time verification of the processing quality of each key process.

[0071] Subsequently, corresponding to the measured results of each online measurement point, the matching parameter compensation logic is embedded. The parameter compensation logic refers to the closed-loop control rules that automatically correct the subsequent machining parameters based on the deviation between the measured accuracy data and the theoretical threshold. Specifically, it includes four categories: tool radius compensation, feed rate adaptive adjustment, cooling strategy adjustment, and tool posture reset. Among them, tool radius compensation is used to correct the dimensional deviation caused by tool wear and indexing positioning errors; feed rate adaptive adjustment is used to dynamically adjust the feed rate of subsequent processes based on the measured cutting load and surface quality; cooling strategy adjustment is used to adjust the pressure and spray pattern of the cutting fluid based on the cutting thermal deformation; and tool posture reset is used to adjust the tool cutting angle of subsequent milling based on the angle deviation of the irregular inclined surface.

[0072] Following this, before the processes involving easily deformable features, a stress-relief idle run is forcibly inserted. This stress-relief idle run refers to the spindle idling at a preset low speed for a set duration, allowing the workpiece to naturally release the internal cutting stress accumulated during the previous roughing process while it is clamped. Specifically, this stress-relief idle run is forcibly triggered before the flange bevel milling process, eliminating potential stress hazards for high-precision machining of easily deformable features. Simultaneously, after each milling process and at locations prone to chip accumulation such as internal drilling and thread machining, auxiliary chip removal commands are forcibly inserted. These auxiliary chip removal commands are used to thoroughly clean the machining process. The machine tool auxiliary control instructions for residual chips in the area and clamping positioning surface include M89 code that triggers the machine tool chip removal function and high-pressure cutting fluid pulse injection instructions, realizing full-process chip control in the machining area. Finally, all process modules, which have been scientifically sorted, inserted with full-process online measurement points, embedded with closed-loop parameter compensation logic, and supplemented with stress relief empty running links and auxiliary chip removal instructions, are integrated into a set of conflict-free, directly recognizable and continuously executed final executable machining strategy sequences.

[0073] In summary, the machine tool processing optimization method based on multi-process coordination provided in this application has the following technical effects:

[0074] By analyzing the irregular surface geometric features of nut parts, structured structural processing requirements are obtained. Then, corresponding optimized process control strategies are matched for each processing requirement. Following the principles of roughing before finishing, external before internal, primary before secondary, symmetrical feature indexing, and postponing easily deformable features, the process sequence is coordinated. At the same time, measurement feedback and parameter compensation logic between processes are inserted. Finally, an executable processing strategy sequence is established and the CNC machine tool is controlled to complete the entire process. This technical solution realizes the collaborative optimization of multiple processes in the entire nut part processing process, effectively reduces part deformation and internal stress accumulation during the cutting process, and prevents the cumulative transmission of processing errors from previous processes to downstream processes. It achieves a synergistic unity of high precision, high pass rate, and high processing efficiency.

[0075] Example 2 is based on the same inventive concept as the machine tool processing optimization method based on multi-process coordination in the previous examples, such as... Figure 2 As shown, this application provides a machine tool processing optimization system based on multi-process coordination, the system comprising:

[0076] The analysis module 11 is used to analyze the structural machining requirements based on the irregular geometric features of the nut part, including the requirements for rough and finish turning of the outer cylindrical surface and end face, the requirements for machining the internal thread bottom hole and chamfer, the requirements for machining the internal thread, the requirements for machining the hexagonal symmetrical surface, and the requirements for machining the flange irregular inclined surface; the matching module 12 is used to match the structural machining requirements with a variety of preset optimized process control strategies to determine the optimized process control strategy corresponding to each machining requirement; the coordination module 13 is used to coordinate the process sequence of the matched optimized process control strategies according to the principles of roughing before finishing, external before internal, primary before secondary, symmetrical feature indexing, and easily deformable features being placed later, and to insert measurement feedback and parameter compensation logic between processes to establish the final executable machining strategy sequence; the execution module 14 is used to control the CNC machine tool to execute each process sequentially according to the executable machining strategy sequence.

[0077] Furthermore, the matching module 12 is also used to perform the following steps: the preset multiple optimized process control strategies include: outer circle / step / end face wide-edge thin chip control strategy, short hole / shallow groove intermittent feed and chip removal control strategy, deep hole segmented retraction and emulsion lubrication strategy, narrow groove / precision step extremely slow feed and elastic deformation elimination strategy, thread machining spindle and feed synchronization strategy, circumferential symmetrical feature indexing micro-cutting and real-time compensation strategy, irregular surface layer-by-layer milling and tool radius compensation strategy, and auxiliary chip removal and stress relief strategy.

[0078] Furthermore, the parsing module 11 is also used to perform the following steps: based on the irregular surface geometric features of the nut part, traverse and identify all machining features in the nut part, classify them according to feature type, including features of revolution, hole features, thread features, planar features and freeform surface features; for each type of machining feature, extract geometric parameters and accuracy requirements; based on the geometric parameters and accuracy requirements, combined with the nut material and blank state, generate a corresponding machining requirement list; prioritize the machining requirement list according to the rule of prioritizing datum features, prioritizing the removal of large allowances, prioritizing high-precision features, and placing easily deformable features last, and output structured structural machining requirements.

[0079] Furthermore, the matching module 12 is also used to perform the following steps: for the rough and finish turning requirements of the outer cylindrical surface and end face, the optimized process control strategy of the matching is to use a wide-bladed tool, set the tool tip at a position lower than the center of the workpiece, and set the main cutting edge angle to form a thin chip layer; use rapid cutting during rough turning and micro-feed during finish turning.

[0080] Furthermore, the matching module 12 is also used to perform the following steps: for the internal thread bottom hole and chamfer machining requirements, the matching optimized process control strategy is to use a drill bit with chip removal grooves, to process in an intermittent cutting manner, and to continuously spray cutting fluid during the machining process; chamfering is performed using a forming tool; for the internal thread machining requirements, the matching optimized process control strategy is to use a carbide threading tool and to strictly synchronize the spindle speed and feed rate; thread machining is performed using a multi-pass method, with the depth of cut decreasing with each pass, and the last pass being a finishing pass.

[0081] Furthermore, the matching module 12 is also used to perform the following steps: For the machining requirements of hexagonal symmetrical surfaces, the optimized process control strategy of matching is to adopt a polar coordinate indexing machining method, with the C-axis as the center and the number of hexagonal faces equally spaced, and to machine one plane after each indexing, using a micro-cutting method; after machining every two planes, the parallelism is detected, and if the parallelism deviation exceeds a preset threshold, the tool radius compensation value is automatically corrected; For the machining requirements of flange irregular inclined surfaces, the optimized process control strategy of matching is to use a ball end mill to mill along the inclined surface contour layer by layer, with the depth of cut of each layer being at the micrometer level, and to enable tool radius compensation; after milling several layers, the actual angle of the inclined surface is detected, and if the deviation between the actual angle and the theoretical angle exceeds a preset threshold, the subsequent toolpath trajectory is recalculated and the tool posture is adjusted.

[0082] Furthermore, the coordination module 13 is also used to perform the following steps: Following the principles of roughing before finishing, external before internal, primary before secondary, symmetrical feature indexing, and easily deformable features being processed later, the matched optimized process control strategies are sequentially sorted to generate an initial process sequence; based on the initial process sequence, online measurement points are inserted between adjacent processes, including diameter and roundness measurements after external diameter finishing, symmetry and parallelism measurements after hexagonal rough milling, pitch error measurements after thread machining, and angle measurements during inclined milling; based on the actual measurement results of the online measurement points, [the following steps are implemented / integrated / implemented]. The parameter compensation logic includes: tool radius compensation, feed rate adaptive adjustment, cooling strategy adjustment, and tool posture reset; before easily deformable characteristic processes, a stress-relief idle run is forcibly inserted, wherein the stress-relief idle run is performed by the spindle at a set speed for a preset duration; after each milling process and at locations where chips tend to accumulate, auxiliary chip removal commands are forcibly inserted, wherein the auxiliary chip removal commands include M89 code and cutting fluid pulse injection; the process sequence after sorting, inserting measurement points, compensation logic, stress relief process, and chip removal commands is integrated to obtain the final executable machining strategy sequence.

[0083] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A machine tool processing optimization method based on multi-process coordination, characterized in that, include: Based on the irregular geometric features of the nut parts, the structural machining requirements are analyzed, including the requirements for rough and finish turning of the outer cylindrical surface and end face, the requirements for machining the internal thread bottom hole and chamfer, the requirements for machining the internal thread, the requirements for machining the hexagonal symmetrical surface, and the requirements for machining the flange irregular inclined surface. The structural processing requirements are matched with a variety of preset optimized process control strategies to determine the optimized process control strategy corresponding to each processing requirement. The matched optimized process control strategies are coordinated according to the principles of roughing before fine processing, external processing before internal processing, primary processing before secondary processing, symmetrical feature indexing processing, and easy-to-deform features being processed later. Measurement feedback and parameter compensation logic between processes are inserted to establish the final executable processing strategy sequence. According to the executable machining strategy sequence, the CNC machine tool is controlled to execute each process sequentially.

2. The machine tool processing optimization method based on multi-process coordination according to claim 1, characterized in that, The preset optimized process control strategies include: wide-edge thin-chip control strategy for outer diameter / step / end face, intermittent feed and chip removal control strategy for short hole / shallow groove, segmented retraction and emulsion lubrication strategy for deep hole, extremely slow feed and elastic deformation elimination strategy for narrow groove / precision step, synchronous strategy for thread machining spindle and feed, indexing micro-cutting and real-time compensation strategy for circumferential symmetry features, layer-by-layer milling of irregular surfaces and tool radius compensation strategy, and auxiliary chip removal and stress relief strategy.

3. The machine tool processing optimization method based on multi-process coordination according to claim 1, characterized in that, Based on the irregular surface geometry of the nut part, the structural machining requirements are analyzed, including: Based on the irregular surface geometry of the nut part, all machining features in the nut part are traversed and identified, and classified according to feature type, which includes features of rotation, hole features, thread features, planar features and freeform surface features. For each type of machining feature, extract the geometric parameters and accuracy requirements; Based on the geometric parameters and accuracy requirements, and combined with the nut material and blank condition, a corresponding list of processing requirements is generated; The processing requirement list is prioritized according to the following rules: priority of basic features, priority of large allowance removal, priority of high precision features, and priority of easily deformable features. The structured processing requirements are then output.

4. The machine tool processing optimization method based on multi-process coordination according to claim 1, characterized in that, Determine the optimal process control strategy for each processing requirement, including: For rough and finish turning of the outer cylindrical surface and end face, the matching optimized process control strategy is to use a wide-bladed tool, set the tool tip below the center of the workpiece, and set the main cutting edge angle to form a thin chip layer; use rapid cutting during rough turning and micro-feed during finish turning.

5. The machine tool processing optimization method based on multi-process coordination according to claim 1, characterized in that, Determine the optimal process control strategy for each processing requirement, including: For the internal thread bottom hole and chamfer machining requirements, the matching optimized process control strategy is to use a drill bit with chip flutes, perform intermittent cutting, and continuously spray cutting fluid during the machining process; chamfering is done using a forming tool; For internal thread machining requirements, the matching optimized process control strategy is to use carbide thread cutting tools and strictly synchronize the spindle speed and feed rate; the thread machining adopts a multi-pass method, with the depth of cut decreasing in each pass, and the last pass is a finishing pass.

6. The machine tool processing optimization method based on multi-process coordination according to claim 1, characterized in that, Determine the optimal process control strategy for each processing requirement, including: For the machining requirements of hexagonal symmetrical surfaces, the matching optimized process control strategy is to use polar coordinate indexing machining method, with the C-axis as the center and the number of hexagonal faces divided at equal angles. After each indexing, one plane is machined using micro-cutting method. After machining two planes, the parallelism is checked. If the parallelism deviation exceeds the preset threshold, the tool radius compensation value is automatically corrected. For the machining requirements of flange irregular bevels, the matching optimized process control strategy is to use a ball end mill to mill along the bevel contour layer by layer, with the depth of cut of each layer being in the micrometer range, and to enable tool radius compensation; after milling several layers, the actual angle of the bevel is detected. If the deviation between the actual angle and the theoretical angle exceeds the preset threshold, the subsequent toolpath trajectory is recalculated and the tool posture is adjusted.

7. The machine tool processing optimization method based on multi-process coordination according to claim 1, characterized in that, Establish the final executable processing strategy sequence, including: Following the principles of roughing before refining, external before internal, primary before secondary, symmetrical feature indexing processing, and postponing easily deformable features, the control strategies of each optimized process obtained by matching are sequentially sorted to generate an initial process sequence. Based on the initial process sequence, online measurement points are inserted between adjacent processes. These online measurement points include diameter and roundness measurement after external cylindrical precision turning, symmetry and parallelism measurement after hexagonal rough milling, pitch error measurement after thread machining, and angle measurement during inclined milling. Based on the actual measurement results of online measurement points, parameter compensation logic is embedded, which includes: tool radius compensation, feed rate adaptive adjustment, cooling strategy adjustment and tool posture reset. Before the easily deformable characteristic process, a stress-relief idling stage is forcibly inserted, wherein the stress-relief idling stage is a main shaft idling at a set speed for a preset duration. After each milling operation and at locations where chips tend to accumulate, auxiliary chip removal commands are forcibly inserted. These auxiliary chip removal commands include M89 code and cutting fluid pulse injection. The sequence of operations, after sorting, inserting measurement points, compensation logic, stress relief, and chip removal instructions, is integrated to obtain the final executable machining strategy sequence.

8. A machine tool processing optimization system based on multi-process coordination, characterized in that, The system is used to implement the machine tool machining optimization method based on multi-process coordination as described in any one of claims 1 to 7, wherein the system comprises: The analysis module is used to analyze the structural machining requirements based on the irregular geometric features of the nut parts, including the rough and finish turning requirements of the outer cylindrical surface and end face, the machining requirements of the internal thread bottom hole and chamfer, the machining requirements of the internal thread, the machining requirements of the hexagonal symmetrical surface, and the machining requirements of the flange irregular bevel. The matching module is used to match the structural processing requirements with a variety of preset optimized process control strategies to determine the optimized process control strategy corresponding to each processing requirement. The coordination module is used to coordinate the process sequence of the matched optimized process control strategies according to the principles of roughing before finishing, external before internal, primary before secondary, symmetrical feature indexing processing, and easy-to-deform features post-processing. It also inserts measurement feedback and parameter compensation logic between processes to establish the final executable processing strategy sequence. The execution module is used to control the CNC machine tool to execute each process sequentially according to the executable machining strategy sequence.

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