制造技术与机床

Research on thermal deformation of ultra-precision machine tools with effect on motion accuracy

CHEN Yi, WANG Zhenzhong, LEI Pengli, SHI Chenchun

2023, (2): 5-11. doi: 10.19287/j.mtmt.1005-2402.2023.02.001

[Abstract] FullText HTML PDF(2012KB)

Abstract:
Large-diameter optical component processing is based on the development of super large-diameter ultra-precision machine tools. For super large diameter ultra-precision machine tools, in the process of large stroke and long working time, the machine’s thermal deformation caused by the guide rail's heat will seriously restrict the straightness of the moving parts and the processing accuracy of the optical components. In this paper, thermal-structural coupling simulation is performed by using ANSYS Workbench software to analyze the thermal deformation of the designed gantry-type grinding machine of large diameter and 5-axis flexible airbag polishing machine, the influence of the heat generated from the guide rail is obtained on the overall thermal deformation of the machine. Temperature-straightness monitoring experiments were conducted on existing grinding and polishing machines to investigate the effect of thermal deformation on the straightness of liquid hydrostatic guideways for grinding machines and linear guideways for polishing machines. In practice, the measurement results show a significant impact on the straightness of the rail movement generated by the oil film heat of the machine tool’s liquid hydrostatic guide.

Modal simulation analysis and experimental study of aerostatic spindle

WANG Yuwei, WU Dongxu, SUO Qi, XIAO Beichuan, WANG Hui

2023, (2): 12-20. doi: 10.19287/j.mtmt.1005-2402.2023.02.002

[Abstract] FullText HTML PDF(2479KB)

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In order to accurately obtain the dynamic modal characteristics of aerostatic spindle, the finite element models of the spindle rotor and the spindle components are established respectively, the boundary conditions of spring and motor constraints added in the finite element model are studied, the modal calculation of the above two finite element models is carried out respectively. This paper makes a comparative analysis of the structural natural frequency, mode of vibration and effective participation mass of each mode under different conditions, and investigates the influence of the housing in the spindle components on the modal parameters of the spindle rotor. The first six natural frequencies of spindle rotor are 1.5 Hz 、277 Hz、279 Hz 、316 Hz、384 Hz、385 Hz. Correspondingly, the first six natural frequencies of the spindle components are 1.5 Hz、259 Hz、270 Hz、281 Hz、352 Hz、363 Hz. The above results include rigid body mode and doublet mode. The comparison results show that the natural frequency of the spindle component decreases due to the increase of its mass. Moreover, the spindle components do not meet the requirements of the symmetrical structure. Therefore, the result of the doublet mode of the spindle components is weakened. To verify the results of finite element simulation analysis, the modal test for spindle components is conducted. Through the comparison between simulation and test, the results show that the simulation results of the spindle rotor are closer to the experimental measurement results, and the first three order deviations are 0.6%, 10.6% and 2.6% respectively. The loading and calculation process of the above simulation boundary conditions and testing methods provide significant reference for further improving the calculation accuracy of modal parameters of aerostatic spindle and revising the dynamic simulation model.

Base on RPR/RP+2R+P robot design for machining aluminum alloy structural parts

LIU Yi, FENG Zongqiang, JIA Xinpei, YAO Jiantao, ZHAO Yongsheng

2023, (2): 21-33. doi: 10.19287/j.mtmt.1005-2402.2023.02.003

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New energy vehicles are the needs of China to cope with the challenges of energy conservation and emission reduction, and have great development prospects. Aiming at the problem that aluminum alloy is mainly used in the body of new energy vehicles, which requires that the machine tool is dexterous and lightweight, the overall stiffness is moderate, and the precision forming of complex surfaces is realized, a five degree of freedom hybrid robot configuration based on RPR/RP plane parallel is proposed. Firstly, the basic configuration of RPR/RP+2R+P 5-DOF hybrid robot is established, the degree of freedom of the hybrid robot is analyzed and calculated, and the initial prototype structure design of the 5-DOF hybrid robot is completed. Secondly, the forward and inverse solutions of parallel and hybrid configuration positions and velocity Jacobian are solved. Then, the pose space of the 5-DOF hybrid robot is solved ; taking the driving force of the branch rod as the optimization index, and the non-interference of the mechanism operation in the working space as the constraint condition, Adams-Matlab co-simulation was used to quantitatively analyze the influence of various structural parameters on the driving force of the branch, and the linear regression algorithm was used for data fitting to complete the scale optimization of the initial prototype. Finally, taking the stiffness of the hybrid robot and its key components as the optimization index, the finite element analysis method is used to realize the progressive structural adjustment of the initial prototype of the 5-DOF hybrid robot. The modal analysis of the whole machine is carried out to obtain the first six-order vibration characteristics of the robot. Under the premise of meeting the stiffness requirements, the new five-degree-of-freedom hybrid robot for aluminum alloy structural parts processing is beneficial to reduce the manufacturing cost and better realize the visualization of machining process. It provides a new idea for the design of hybrid robot for light and thin structural parts processing.

Optimization of industrial robots off-line programming for grasping tasks

ZHAO Weixin, ZHANG Wenchao, WANG Mingwei, WANG Chenxi, JIANG Han, LI Da

2023, (2): 34-39. doi: 10.19287/j.mtmt.1005-2402.2023.02.004

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In order to improve the operation efficiency of the robot and reduce the production cost, the off-line programming for grasping process of the industrial robot is optimized. This Paper takes the IRB1200 robot as the research object. Firstly, the kinematics model of the robot is built by the forward and inverse kinematics. Secondly, the processing technology and the running trajectory are analyzed. Thirdly, the simulation platform is built in Tecnomatix environment to analyze the TCP speed under different motion conditions. Finally, the off-line programming of the robot before and after the speed are compared. Consequently, the processing time can be shortened by about 10%. The experiments have verified that the optimization method can improve the motion efficiency of industrial robots, and reduce the work energy consumption.

Photoelectrochemical mechanical polishing device design

ZHANG Gaozhen, ZHU Xianglong, DONG Zhigang, KANG Renke, ZHAO Yang

2023, (2): 40-45. doi: 10.19287/j.mtmt.1005-2402.2023.02.005

[Abstract] FullText HTML PDF(2054KB)

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In response to the processing needs of photoelectrochemical mechanical polishing of the third-generation semiconductor material gallium nitride (GaN), an optoelectronic chemical mechanical polishing (PECMP) device with ultraviolet light irradiation, voltage loading and mechanical polishing functions was developed. The polishing disc unit with ultraviolet light directly shining on the surface of the GaN wafer, and the electrical circuit with stable loading voltage in the processing area and insulated from the device was designed. The driving mechanism was designed which has independent rotation of polishing disc and workpiece disc, reciprocating movement of polishing disc and adjustable loading of polishing pressure. The three-dimensional model of the whole PECMP device was established, and the structure of key components such as polishing disc and gantry was optimized through static analysis and modal analysis. The PECMP polishing device was built and the performance test was carried out. In the test, the applied light intensity was 0~200 mW·cm⁻², the voltage size was 0~10±0.1 V, the insulation resistance was 150 MΩ, the polishing disc speed was 10~100 r/min, the workpiece speed was 10~200 r/min, the polishing disc reciprocating moving speed was 1~100 mm/s, and the pressure loading range was 0~200 N, which met the PECMP processing needs of 2-inch GaN wafers.

Study on the increment forming properties of TA1 sheet based on ultrasonic assistance

HAO Yongxing, WEI Yabo, GAO Yuanhao, SONG Yipeng, LIU Yahui

2023, (2): 46-51. doi: 10.19287/j.mtmt.1005-2402.2023.02.006

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Titanium and its alloys are widely used in various fields because of their advantages such as low density, high specific strength and good biocompatibility. In this paper, the ultrasonic assisted incremental forming process was applied to the TA1 incremental forming process of titanium alloy plate, using ABAQUS finite element software simulation of ultrasonic assisted incremental forming process. And the reason of the forming force reducing in the forming process was analyzed, the influence of different vibration parameters and process parameters on forming force of TA1 titanium alloy sheet was studied. The results show that ultrasonic vibration can significantly reduce the forming force, which provides relevant basis for the application of ultrasonic vibration in the increment forming of TA1 titanium alloy sheet. It is of great significance to expand the application of titanium alloy sheet increment forming process.

Modeling and simulation of milling force in side milling of profile walled surface of titanium alloy

LI Anhai, ZHU Xiaoli, ZHANG Rufeng, GAI Shaolei

2023, (2): 52-56. doi: 10.19287/j.mtmt.1005-2402.2023.02.007

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The side milling of the profile walled of titanium alloy parts is generally processed with solid carbide end mills. Due to the influence of cutting forces, the machining process is difficult to control and will produce part deformation. Modeling and predicting of the milling forces is an effective method to control the machining deformation. Through the summation and synthesis of micro element cutting force vector of cylindrical spiral end mill, the transient cutting force prediction model in the side milling process of integral end mill was established. Both the shearing and ploughing force coefficients of the cylindrical spiral end mill for titanium alloy side milling test were obtained by using the milling force identification test under different feed speeds and the numerical linear fitting of the average cutting force test data. The instantaneous cutting forces of four edge solid carbide end mills with different cutting parameters were calculated, and the validity of the simulation model is verified by the side milling experiments of titanium alloy. This will provide a theoretical basis for the formulation and optimal selection of side milling process parameters of titanium alloy structural parts.

Design and application of weak rigid profile milling tool

YUAN Xinman, HU Zhiqin, YUAN Tian, WANG Zhichao

2023, (2): 66-72. doi: 10.19287/j.mtmt.1005-2402.2023.02.009

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In order to meet the assembly requirements, the skeleton assembled by the web parts usually needs to be machined twice. Among them, the weakly rigid frame edge assembly surface is repaired due to chatter, deformation, etc, causing frequent milling damage problems, which seriously affects the assembly quality . Therefore, starting from the influence of tool structure on profile milling force, this paper designs a dense-pitch milling cutter for weakly rigid profile machining, and conducts cutting parameter matching tests based on the tool. Dimensionally optimizes cutting parameters, and calculates the optimal cutting parameters of the tool under two responses. The results show that under the optimized cutting parameters, the cutting force of profile milling is 43 N, and the surface roughness is Ra 1.04 μm.

Curved edge design of forming milling tool for large wind power transmission gear

LI Haogang, WANG Xiaoming, ZHANG Zechen, LIU Bo, ZHOU Zongming, CHEN Yun, LI Changhe

2023, (2): 57-65. doi: 10.19287/j.mtmt.1005-2402.2023.02.008

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The gear disk milling tool based on the forming principle is the necessary tool for producing large-scale wind power transmission gears. However, due to the influence of the machining principle error, the traditional gear milling tool can only process specific types of gears, and the versatility of the cutter is poor. The traditional tool profile cannot guarantee the machining accuracy and service life of the gear to be machined, and cannot maximize the principle advantages of form milling. In this paper, the mathematical model of the actual profile curve of the gear involute is established. Based on the relative motion track of the top angle of the conjugate rack, the equation of the tooth root transition curve is established. According to the relative position of the tooth root transition arc space, the design methods of different forms of tooth profile curves are reconstructed. Based on the inverse projection method, the numerical model of the blade edge curve is established with the parameters of the gear to be machined as variables. According to the principle of the blade space envelope, the design method of the profile curve of the indexable gear disk milling cutter is reconstructed. The numerical analysis of gear tooth profile and blade profile curve is carried out, and the main forms of large wind power transmission gear tooth profile curve and indexable gear disk milling tool edge profile curve are studied.

Research and application of intelligent manufacturing predictive maintenance standard system

WANG Chengcheng, WANG Jinjiang, HUANG Zuguang, XUE Ruijuan, ZHANG Peisen

2023, (2): 73-82. doi: 10.19287/j.mtmt.1005-2402.2023.02.010

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Predictive maintenance is an important technology to predict the future working conditions of equipment through real-time monitoring of its operating status, and to realize fault diagnosis, life prediction, equipment maintenance and management. It is one of the typical applications of artificial intelligence in intelligent manufacturing. However, the confusion of terms and definitions related to predictive maintenance, the lack of communication and integration interfaces between systems, and the difference between monitoring diagnosis scheme and prediction algorithm have seriously hindered the application of predictive maintenance. Therefore, this paper analyzes and discusses the requirements of predictive maintenance standards from three aspects: predictive maintenance technology application, standard system, and standard content, constructs a predictive maintenance standard system covering basic common standards, key technical standards, and industrial application standards, and analyzes the current standards and the future direction of standardization. Based on the research in this paper, it is hoped that standards researchers can further develop standards related to data, evaluation, remaining life prediction, and maintenance management, and effectively promote the development of predictive maintenance technology and the digital transformation of equipment.

Construction and application of knowledge graph in mechanical fields based on deep learning

CUI Shuo, ZHANG Chunyan, JIA Jiale, ZHANG Chengdong, ZHANG Shengwen, CHEN Kai

2023, (2): 83-89. doi: 10.19287/j.mtmt.1005-2402.2023.02.011

[Abstract] FullText HTML PDF(2063KB)

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Aiming at the problem that it is difficult to reuse the design information stored in a decentralized form within the enterprise, the design model library, and the text resource library are integrated to build a knowledge graph in the field of mechanical design. Obtain the required domain knowledge from historical model libraries and documents through computer vision and other technologies: for model library data, clustering algorithms are used to reduce map node redundancy; A new machine ALBERT pre-trained model is proposed to design parameters for universal ALBERT, which is used as the semantic coding layer of text, Bi-LSTM as the label prediction layer, CRF as the overall label optimization layer, and the entity recognition model is built. For the relationship extraction model, the character encoding layer is shared, the CNN layer is added to classify the text relationships, and the unstructured information is converted into a structured triple, which is stored in the graph database after entity alignment. A computer-aided design visualization system is established based on the completed map, which aims to provide various functions such as entity query and knowledge quizzes to improve product design efficiency.

Research on resource sharing technology and platform development of mould manufacturing in cloud manufacturing environment

KUANG Chaopeng, TAO Jianhua, LI Tingtai, CHEN Bin, MA Yao, WANG Wei

2023, (2): 90-96. doi: 10.19287/j.mtmt.1005-2402.2023.02.012

[Abstract] FullText HTML PDF(1464KB)

Abstract:
Aiming at the problems of long production cycle, few resources, low equipment utilization rate, lack of communication and cooperation among enterprises in different regions, and lack of accumulation and inheritance of manufacturing experience and knowledge, the cloud manufacturing mode is introduced, define and classify mold manufacturing resources, build a mold enterprise manufacturing resource sharing process model for customer orders, establish a mold manufacturing resource sharing cloud service resource library, and develop an intelligent manufacturing cloud platform system for mold processing. The results show that based on the cloud platform, all franchised enterprises have more diversified ways to obtain mold orders, richer production and manufacturing methods, and more convenient access to industry information, which is conducive to the matching of supply and demand between enterprises and improve the competitiveness of enterprises.

Research on sliding characteristics of eccentric cam roller movable tooth transmission based on MATLAB

WANG Ran, WANG Shijun, DU Yaning, QI Na, ZHENG Surui

2023, (2): 97-103. doi: 10.19287/j.mtmt.1005-2402.2023.02.013

[Abstract] FullText HTML PDF(1926KB)

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The contact of the roller -tooth transmission is composed of two high sidewalks and a low vice. The high vice is relatively sliding from the different cut speed of the contact point. Based on the structural characteristics and working principles of rolling living tooth transmission, this article derives the sports model and sliding model of rolling living teeth, and proposes a new numerical modeling method based on the principle of speed decomposition. The effects of design parameters on the sliding rate and slippery ratio, the results show that as the rolling rolling ratio of the living teeth increases, the ratio of slippery roller is reduced first. For parameter research, the sliding ratio is increased with the ride radius and transmission ratio of the rumor. Increase, decrease with the increase of the radius and eccentric spacing of the living tooth. The changes in the transmission ratio and the radius of the roller teeth are less impact on the slip ratio, and the changes in the eccentric spacing and the radius of the rotor have a greater impact on the slippery ratio. The results of the research provide theoretical guidance to reduce friction and improve the driving efficiency of rolling living teeth.

Nonlinear adaptive backstepping control of magnetic levitation system of electrically excited linear motor

XING Yixin, LAN Yipeng, LEI Cheng

2023, (2): 104-108. doi: 10.19287/j.mtmt.1005-2402.2023.02.014

[Abstract] FullText HTML PDF(1818KB)

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In order to improve the performance of the magnetic levitation platform control system of NC machine tool driven by electrically excited linear motors (EELM), a nonlinear adaptive backstepping control method is proposed. The structure and operation mechanism of EELM are studied. The stator of EELM is composed of iron core and excitation winding, and the mover is composed of iron core and armature winding. It is fixedly connected with the feed platform of NC machine tool to drive the movement of the platform. The suspension of the platform is realized by the suspension of the excitation magnetic field on the unilateral magnetic pulling platform of the mover iron core; The mathematical model and state equation of the control system of the EELM maglev platform are established; For the uncertain disturbance existing in the operation of the magnetic levitation platform of electrically excited linear motor, The unknown disturbance is estimated by designing a nonlinear adaptive backstepping controller,and the Lyapunov theory is used to verify the stability of the system. The computer simulation of the control system is carried out with MATLAB/Simulink to verify the effectiveness of the proposed method.

Machine-tool structure design with composite function of adding and subtracting materials

WU Ying, LI Jindong

2023, (2): 109-113. doi: 10.19287/j.mtmt.1005-2402.2023.02.015

[Abstract] FullText HTML PDF(2023KB)

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In recent years, according to the development trend of material adding and subtracting technology, it is necessary to realize the material adding and subtracting function on the same CNC machine tool. A set of composite ram structure is designed to realize the efficient combination and integration of the 3D printing head and the machining head. The forming function of the workpiece is realized through the additive function of 3D printing technology, and then the designated part is processed through the machining technology, thus realizing the one-stop forming and processing function of the predetermined workpiece. This structural design has been verified by practical application on a gantry machine tool with compound functions of adding and subtracting materials, which greatly reduces the handling of workpieces in the production process and avoids the workpiece clamping deviation caused by multiple positioning and clamping. The results show that the structural design is reasonable, especially for machine tools with large and medium-sized components. This structure greatly simplifies the structural complexity of the equipment, reduces the direct material investment of the equipment, but also increases the overall reliability, efficiency and price-performance ratio of the products.

Optimization of process parameters for cold extrusion forming of threaded hole based on response surface method

WU Yanyun, MU Tianchi, ZHANG Dongmin, ZHOU Weimin, SHU Tiantian

2023, (2): 114-118. doi: 10.19287/j.mtmt.1005-2402.2023.02.016

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FDS chipless self-tapping screws are widely used in the new energy automobile manufacturing industry as a thin-plate connection fastener. Aiming at the influence of the quality of threaded holes on the strength of self-tapping screws, the Box-Behnken method is used for self-tapping screws. Research on cold extrusion process. Through the combination of response model, numerical simulation and experiment, the relationship between frustum angle, extrusion speed, frustum height and friction coefficient, forming quality and forming load was studied, and the optimal parameter combination was obtained: frustum angle. The angle is 20.16°, the height of the frustum is 6.12 mm, the extrusion speed is 616.28 r/min, and the friction coefficient is 0.36. It is verified through experiments that the thread connection strength under this optimal parameter is good and the thread profile is full, which can effectively reduce the forming load.

Study on U-axis mechanism design and parameter calculation

ZHAO Huibo, LI Hanwei, YU Guodong, YANG Xiuli

2023, (2): 119-122. doi: 10.19287/j.mtmt.1005-2402.2023.02.017

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A U-axis mechanism based on 2K-H (C) type planetary differential was designed to process turning contours in large/heavy workpieces or slender shafts with equal-diameter or variable-diameter sections. The working principle of the mechanism was analyzed by taking facing head as an example, providing a theoretical foundation for the U-axis feeding parameter design. Deformation systems were also proposed to meet the working requirements of different situations.

Rolling bearing fault diagnosis based on RCMDE and extreme learning machine

LIU Yunbin, QIAN Jun, PAN Shuming

2023, (2): 123-126. doi: 10.19287/j.mtmt.1005-2402.2023.02.018

[Abstract] FullText HTML PDF(1335KB)

Abstract:
Aiming at the low recognition rate of rolling bearing fault signals, a fault diagnosis method based on refined composite multiscale dispersion entropy (RCMDE) and extreme learning machine (ELM) is proposed. Firstly, extracting 20 scales of refined composite multi-scale discrete entropy from the original vibration signal and constructing a fault feature set based on this, and then using ELM to identify fault types. The validity of the proposed method was verified by bearing data from Case Western Reserve University. Finally, the proposed method is compared with MPE-ELM. The comparison results show that the proposed fault diagnosis method has higher classification accuracy.

Geometric parameter and mechanical property analysis of flexible polishing wheel with superhard abrasive for blisk

SU Yuhao, JIAO Lei, HE Zhiqiang, XIE Zhuoqun

2023, (2): 127-133. doi: 10.19287/j.mtmt.1005-2402.2023.02.019

[Abstract] FullText HTML PDF(1377KB)

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Blisk is a key component of aeroengine. NC polishing with super-hard abrasive flexible polishing wheel has become an effective way to replace manual polishing and improve the surface quality of blisk. In this paper, the equivalent diameter and polishing force model of the flexible polishing wheel with complex generatrix super-hard abrasive is analyzed, and established to optimize the geometric parameters and mechanical properties of the polishing process. Among them, the geometric parameters of the polishing wheel are converted into mechanical parameters by force measuring instrument, the equivalent parameter calculation model is established, and the equivalent diameter of the polishing wheel is obtained by inverse deduction of the relationship, so as to improve the polishing measurement deviation caused by the dynamic diameter measurement inaccuracy. A single factor orthogonal experiment was designed to measure the polishing force under different processing parameters, and the influence of each factor on the polishing force. Then, under the stable working state of the polishing wheel, an empirical model of the polishing force was established, which can be used to predict the real polishing force in the NC polishing process of the blisk. The experiment proves that the accuracy of equivalent diameter is 2.02% higher than that of dynamic measurement, and the actual value of polishing force and model fitting value fit very well, with the correlation coefficient reaching 0.999.

Quality control and prediction of drawing forming of automotive back door inner panel based on NSGA-II algorithm

TAO Zhe, JI Ning

2023, (2): 134-140. doi: 10.19287/j.mtmt.1005-2402.2023.02.020

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In order to avoid forming defects such as wrinkling and cracking during the stamping of automobile cover parts, a non-ranking genetic algorithm (NSGA-II) based on elite strategy was proposed to optimize the stamping process parameters and realize the control and prediction of stamping forming quality. The forming process parameters such as blank holder force, friction coefficient, forming force and die clearance were taken as test factors, and the maximum thickening rate and the maximum thinning rate during drawing deformation were taken as quality control objectives. Latin hypercube sampling method and combining with CAE analysis technology to establish the test sample, build between stamping process parameters and forming quality control target of the response surface model, based on the NSGA - II algorithm was obtained in constructing the response surface model of a set of optimal process parameters meet the forming quality combination, at the same time, the forming quality of forecast is given. The actual stamping die test results prove the effectiveness of the method proposed in this paper, which provides a set of reference methods for the quality control and prediction of automobile cover parts.

Numerical simulation of temperature field of 316L stainless steel in additive manufacturing by Workbench

LIU Haocheng, LV Yanming, HUANG Qiang, YU Jiahao

2023, (2): 141-146. doi: 10.19287/j.mtmt.1005-2402.2023.02.021

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The numerical model of the temperature field of wire arc additive manufacturing is simulated by Workbench. Through combining birth and death method with the mobile heat source, the temperature field under different process parameters is established and solved. The results show that the heat accumulation effect in the multi-layer additive process of formed parts is enhanced layer by layer under fixed input conditions. Under the same heat input, the temperature of midpoint on weld bead increases from 2 354.9 ℃ in the first layer to 2 879.7 ℃ in the tenth layer. The heat accumulation can be reduced by controlling the cooling time and changing heat input. The interlayer temperature is controlled below 600 ℃. And the maximum temperature of the additive process is reduced by 10 % by changing the layer-by-layer heat input parameters.

The poka-yoke technology research of NC tool compensation parameters setting

ZHAO Guoqiang

2023, (2): 147-151. doi: 10.19287/j.mtmt.1005-2402.2023.02.022

[Abstract] FullText HTML PDF(1023KB)

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The problems of tool damage and no effective control means often occur in the production site due to manual setting error of NC tool compensation parameters. In view of the above problem, one programmable poka-yoke method of tool compensation parameters manual setting for Siemens NC systems is presented, and a kind of universal poka-yoke NC program for tool compensation parameters setting is also developed. Finally the program is verified in the production site. It is proved that the method is simple and easy to use, cost-effective. The automatic poka-yoke purpose of tool compensation parameters manual setting is realized.

Research on integrity check technology based on PMI domain knowledge graph

WANG Yanyan, ZHANG Chunyan, ZHANG Shengwen, CHEN Shihui

2023, (2): 152-159. doi: 10.19287/j.mtmt.1005-2402.2023.02.023

[Abstract] FullText HTML PDF(4308KB)

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A new completeness checking technique based on PMI domain knowledge map was proposed for solving the problems of non-uniform form of PMI annotation of product MBD 3D model, error-prone annotation, and difficulty of manual checking. The technique uses a top-down approach to construct the PMI domain knowledge map, constructs the rules for completeness checking by using SWRL rules, checks the redundancy relationship of annotation, substitution relationship of annotation, and contradiction of annotation in three aspects, and realizes knowledge reasoning by combining with Java Web technology. Finally, the feasibility of the method was verified by taking the frame of a marine diesel engine as the object. The technique greatly shortens the checking time and reduces design error rate, and improves the design efficiency of the staff.

Multi axis synchronous adaptive control of generating gear grinding based on electronic gearbox

HAN Jiang, ZHOU Guangxin, XIA Lian, HUANG Xiaoyong, LI Yanqing, TIAN Xiaoqing

2023, (2): 160-166. doi: 10.19287/j.mtmt.1005-2402.2023.02.024

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Generating gear grinding is an important high-speed and high-precision gear processing technology. CNC gear grinding machine tool and workpiece synchronous control, namely electronic gear box control precision largely determines the precision of gear machining. In order to reduce the influence of grinding force changes, external disturbances and other factors on the synchronization control accuracy in actual working conditions, an adaptive synchronization control method of electronic gearbox is proposed to improve the anti-interference of the core control system of gear grinding. Firstly, a multi axis linkage model based on electronic gearbox is established; Then, an extended Kalman observer with adaptive function is studied to observe the grinding force generated in the multi axis machining process. The system processes the observation results, and designs feedforward based on the calculation results to compensate the deviation generated by the grinding force; Finally, compared with the observation effect of traditional observers in the simulation system, the simulation and experiment show that this method can effectively reduce the helix deviation and pitch deviation of gears, and ensure the anti-interference of the system.

Progressive prognosis rupture prediction based on Johnson-Cook damage criterion based on principal component regression

WANG Baichao, XU Hu, ZHANG Litong, ZHANG Hongming, WANG Huidong

2023, (2): 167-174. doi: 10.19287/j.mtmt.1005-2402.2023.02.025

[Abstract] FullText HTML PDF(1411KB)

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In order to be able to more accurately predict the height of fracture when the sheet metal is formed, this paper takes the Johnson-Cook damage criterion as the standard, adopts the principal component analysis method, measures the fracture data by orthogonal experiment method, and uses SPSS and MALTAB data analysis software to specifically interpret the impact of the six process parameters of tool diameter, layer spacing, forming angle, sheet thickness, forming height and part size on the fracture. Construct a predicted linear regression equation for progressively formed sheet rupture. The results show that the principal component regression model based on the measured data of 16 workpieces predicts that the fracture height of the two test pieces is −10.753 0 mm and −10.815 0 mm, respectively, and the error between the actual fracture height is only 3.84% and 6.14%. It can be seen that the plate fracture model has a certain feasibility and accuracy, which can better predict the height of sheet fracture and prevent forming defects as much as possible.

Research on measurement method of rotation accuracy of angular contact ball bearing without assembly

JI Ye, ZHENG Haotian, WANG Dongfeng, MA Xinzhong

2023, (2): 175-180. doi: 10.19287/j.mtmt.1005-2402.2023.02.026

[Abstract] FullText HTML PDF(1389KB)

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The rotation accuracy detection of angular contact ball bearing(ACBB) needs to be carried out in the assembly, which increases the detection process. Bearings that do not meet the design requirements need to be re-matched with rings. By analyzing the contact state of the rings and according to the geometric relationship, an analytical model of the accuracy parameters of the rings is established. Taking 7006-ACBB as an example, the accuracy parameters of 9 circumferential uniform points of the rings are measured, and the radial runout of the finished bearing is calculated, which is consistent with the detection result of the rotating accuracy measuring instrument. In order to obtain the variation law of rotation accuracy, four kinds of curves are used to fit the contour, and the radial runout changes are calculated respectively. The contour obtained by linear fitting function is close to the detection result. The relationship between the rotation accuracy and the groove radius of curvature, the groove bottom diameter and the wall thickness difference are studied. The distribution law of the groove bottom diameter has the most obvious effect on the rotation accuracy, and the groove radius of curvature has little effect. The method in this paper can achieve the rotation accuracy of the finished bearing under the condition of only detecting the precision parameters of the ferrule, which is not only conducive to the matching of the rings, but also avoids the repeated disassembly and assembly of the rings.

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