A detachable design method of large-sized structure for heavy duty machine tool based on joint surface dynamics characteristic analysis

2019 ◽  
Vol 233 (13) ◽  
pp. 4476-4489 ◽  
Author(s):  
Qiang Cheng ◽  
Baobao Qi ◽  
Zhifeng Liu ◽  
Guojun Zhang ◽  
Caixia Zhang ◽  
...  
Keyword(s):  
Dynamic Characteristics ◽  
Machine Tools ◽  
Design Method ◽  
Contact Stiffness ◽  
Joint Surface ◽  
Optimized Design ◽  
Heavy Duty ◽  
Characteristic Analysis ◽  
Structural Part ◽  
Stiffness And Damping

Heavy duty and ultra-heavy duty machine tools are used to manufacture large parts or super large parts in aerospace, ship, transportation, and energy industries. The weight of a structural part of ultra-heavy duty machine tools will reach more than 100 tons, because of which both manufacturing and transportation become very difficult. In this paper, a detachable design method for large-sized structures of heavy duty machine tools is presented. The proposed method aims to make large-sized structure into several detachable sections that can be bolted together in order to be casted and transported and remanufactured more easily. To analyze the influence of the joint surface, a three-dimensional fractal contact model based on the influence of domain expansion factor is used to identify stiffness and damping of the joint surface. On the basis of the analysis of the dependence of contact stiffness and damping of joint surface on dynamic characteristics of structural part, a detachable optimization model of a super span beam is established, and the particle swarm optimization algorithm is adopted to carry out the optimization. After that, the dynamic characteristics of the optimized design is analyzed and verified by finite element analysis. Based on the simulated verification, a detachable beam of heavy duty gantry machine was designed by the proposed method and verified by the field test. The illustration example shows that the large span beam can be detached into three sections that can be bolted together by high strength bolts, and it also has satisfied performance.

The Dynamic Characteristic Analysis of Full Hydraulic Steering System in Large Mining Truck

2013 ◽  
Vol 433-435 ◽  
pp. 59-62
Author(s):  
Jiang Yong
Keyword(s):  
Dynamic Characteristic ◽  
Dynamic Characteristics ◽  
Steering System ◽  
Technical Support ◽  
Heavy Duty ◽  
Characteristic Analysis ◽  
Hydraulic Steering

The SGA170 mine truck was used as research object, the full hydraulic steering system and it's dynamic characteristics was simulated by the AMESim, the characteristics and simulation curve of the steering system and the steering mechanical under various conditions was obtained, which provided theoretical reference and technical support to the design and analysis of full hydraulic steering system of the heavy-duty mine truck, and has important value in the engineering.

Dynamic Characteristics Analysis for Seismic Vibrator

2014 ◽  
Vol 472 ◽  
pp. 48-55
Author(s):  
Li Qiang An ◽  
Fan Peng Kong ◽  
Yong Fang Wang
Keyword(s):  
Modal Analysis ◽  
Dynamic Characteristics ◽  
Data Transfer ◽  
Element Model ◽  
Dynamics Simulation ◽  
Characteristic Analysis ◽  
Characteristics Analysis ◽  
Stiffness And Damping ◽  
Multi Body ◽  
Seismic Vibrator

Seismic vibrator is one of the most widely used equipments in exploration field. In recent years, with the development of exploration field, as well as the growing needs of high quality seismic data, the seismic vibrator's tonnage has increased a lot, which makes the stress of the vehicle frame very complicated in working state. And some local structure of the vehicle frame often appears crack phenomenon in working state. Therefore, the dynamic characteristic analysis is essential to the Seismic vibrator. In this paper, the finite element model of vehicle frame is established by ANSYS software. Through the modal analysis, the natural frequencies are obtained, and each vibration modes are analyzed. On the basis of the modal analysis, the modal neutral file of the vehicle frame is established. Using the data transfer function between ANSYS and ADAMS, the rigid-flexible coupling multi-body model is built for the dynamics simulation of the seismic vibrator. In this model, the stiffness and damping of air springs, hydraulic oil and soil are simulated by the spring-damper in the ADAMS software. The dynamic characteristics of vehicle frame under excited forces with different amplitude are obtained and analyzed. The stresses for some of the hot spots of the vehicle frame are extracted, which can be used to analyze the dynamic failure of the vehicle frame.

Dynamic Characteristic Analysis and Structural Modification of a 5-Axis Horizontal Machining Center Considering Joint Surface

2011 ◽  
Vol 697-698 ◽  
pp. 513-516
Author(s):  
Y.G. Shi ◽  
Xing Yu Zhao ◽  
Li Qiang Zeng ◽  
H.Y. Wang ◽  
Da Wei Zhang
Keyword(s):  
Finite Element ◽  
Dynamic Characteristic ◽  
Dynamic Characteristics ◽  
Structural Modification ◽  
Weak Link ◽  
Joint Surface ◽  
Element Calculation ◽  
Characteristic Analysis ◽  
Machining Center ◽  
Surface Dynamic

In order to make a 5-axis linkage horizontal machining center have better dynamic characteristics, considering the influence of joint surface, dynamic characteristic analysis is conducted to the machining tool. Based on finite element modal analysis results, the weak link is found and optimized. Through the finite element calculation and analysis, the structure rigidity obviously raises after optimization. This offers a new idea on how to improve the rigidity of complete machine of machining tool for later research.

scholarly journals Research on the micro and dynamic characteristics of combination surface based on fractal theory

2020 ◽  
Vol 11 (1) ◽  
pp. 1-27
Author(s):  
Chunxia Zhu ◽  
Zhibiao Yan
Keyword(s):  
Theoretical Analysis ◽  
Dynamic Characteristics ◽  
Optimization Design ◽  
Contact Stiffness ◽  
Fractal Theory ◽  
Joint Surface ◽  
Tangential Contact ◽  
Surface Parameters ◽  
Mechanical Joint ◽  
Texture Parameters

Abstract. The dynamic characteristics of the mechanical joint surface are important aspects of the dynamic theoretical analysis and optimization design of the machine tool. In this paper, the typical mechanical joint surface is taken as the research object. Through the combination of theoretical analysis and experimental analysis, the dynamic characteristics of typical joint surface parameters with different surface textures and the influence of texture parameters on the dynamic characteristics of the joint surface are studied. Based on the Hertz elastic contact theory and the contact fractal theory, the normal and tangential contact fractal models of the joint surface are derived, and then a mathematical model of the joint surface normal and tangential contact stiffness considering the domain expansion factor is established. The influence of surface texture parameters on the dynamic characteristics of the surface is further studied according to the model. In addition, the design of the experimental device and experimental scheme design are completed by the contact resonance method and the ERA algorithm, and the joint surface parameter identification experiment with texture is conducted. The normal and tangential frequency response functions of the joint surface, the dynamic characteristic parameters of the joint surface and the influence law of the joint surface parameters on the contact characteristics are obtained through the dynamic test analysis technology.

Dynamic Characteristics Optimization of Joint Interface of Machine Tool Based on Porous Oily Materials

2014 ◽  
Vol 709 ◽  
pp. 63-67
Author(s):  
Jian Feng Ma ◽  
Qiang Li ◽  
Ji Kun Feng ◽  
Liang Sheng Wu
Keyword(s):  
Porous Material ◽  
Machine Tool ◽  
Dynamic Characteristics ◽  
Machine Tools ◽  
Unit Area ◽  
Test System ◽  
Joint Interface ◽  
Characteristic Parameters ◽  
Damping Characteristics ◽  
Stiffness And Damping

The joint interface plays a significant role in machine tools and other machineries. A novel type of joint which consists of oily porous material was proposed in the paper. A test system for identifying the unit area dynamic characteristic parameters of Fe-based joint interfaces were represented. The stiffness and damping parameters were compare to the conversional structures. The result showed that the joint which contains an oil film interlayer formed by porous and steel was superior to the joint with non-media formed by steel in stiffness and damping characteristics. In the case of the same preload, the former’s stiffness is increased by about 50 %, and the damping is increased about five to six times.

scholarly journals Vibration Characteristics of Heavy-Duty CNC Machine Tool-Foundation Systems

2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Yang Tian ◽  
Qilin Shu ◽  
Zhifeng Liu ◽  
Yujie Ji
Keyword(s):  
Machine Tools ◽  
Frequency Response Function ◽  
Vibration Characteristics ◽  
Cnc Machine Tools ◽  
Joint Surface ◽  
Cnc Machine Tool ◽  
System Dynamics Model ◽  
Heavy Duty ◽  
Cnc Machine ◽  
Dynamics Model

Vibration characteristics of heavy CNC machine tools are directly affected by their foundations. To analyze vibrations of heavy CNC machine tools caused by internal and external loads, a system dynamics model of a rigid-flexible coupled heavy-duty CNC machine tool-foundation system was established based on the multibody transfer matrix method. Since joint surfaces can seriously affect the accuracy of system mechanics models, the substructure synthesis method was first used to establish a dynamic model of the joint surface. The frequency response function was then used to identify model parameters. Moreover, to improve the accuracy of parameter identification of the joint surface, a residual frequency compensation function was used to reconstruct the frequency response function. Finally, the multibody system model was implemented by combining surface elements. To verify the system dynamics model, an experimental model of the heavy-duty machine-foundation system was built, taking into consideration joint surface factors, and the theoretical model was validated by comparing theoretical, simulation, and experimental results. Using the theoretical model, the influence of different forms of concrete foundations, materials, and soil properties on the vibration characteristics of heavy-duty CNC machine tools was analyzed, thus providing a theoretical basis for optimizing and improving CNC machine tools.

Analysis on Dynamic Characteristics of the Linear Rolling Guide Pair and Experiment

2011 ◽  
Vol 52-54 ◽  
pp. 989-994
Author(s):  
Xiao Peng Li ◽  
Wei Nie ◽  
Bang Chun Wen
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Dynamic Characteristics ◽  
Machine Tools ◽  
Great Influence ◽  
Element Model ◽  
Joint Surface ◽  
Study Results ◽  
Rolling Guide ◽  
The Finite Element Model

Linear rolling guide is one of the most essential parts of the NC modern machine tools, and they play a significant supporting and guiding role in machine tools components. Especially, the joint surface between guides has great influence on machine's dynamic characteristics. According to this, in this work, taken the Japanese THK Corporation's SNS35LR rolling guide as specific study object, the finite element model of guide pair has been established with the joint surface influence considered. And by the method of the theoretical analysis with the experimental confirmation combined; the dynamic characteristics of the linear rolling guide pair's were studied relatively. Thus, the theoretical model and the finite element model established in this paper can be confirmed by the experiment. It has been found that the theoretical models established are consistent with the results of experiment. This study results can provide useful guidance for the dynamic analysis and the structure optimization of CNC machine tools, and numerical simulation in engineering and design in the development of such machines with rolling guide used.

Dynamic Characteristics of a Machine Tool at Working Positions in Operating Test

2011 ◽  
Author(s):  
Huimin Dong ◽  
Yang Tan ◽  
Delun Wang ◽  
Yali Ma
Keyword(s):  
Machine Tool ◽  
Dynamic Characteristics ◽  
Machine Tools ◽  
Dynamic Properties ◽  
Vibration Energy ◽  
Testing Method ◽  
Spring Element ◽  
Machining Center ◽  
Brick Element ◽  
Stiffness And Damping

A machine tool is an assembly structure fitted by some moveable substructures, which the relative motion between the substructures creates normal and limit operating positions. Along with the substructures moving, the distributions of masses, stiffness and damping of the machine in space vary, leading to variety of structure distributions and dynamic properties. For exploring the dynamic properties distributions of machine tools, this paper presents a testing method under practical operational excitations, which is under operating excitations from remaining unbalanced value in the spindle, and collecting vibration signals of time and frequency at the spindle foreside at working positions. To identify resonance characteristics, a judging matrix is established by comparing vibration energy and vibration amplitude at 1st octave. By this method, MDH50 active pole horizontal machining center is tested, and the dynamic characteristics is determined. It reveals that dynamic characteristics of resonance come from the substructure independent resonance and their superposition in operating excitation. For verifying this result, FEA is conducted, in which 20 nodes brick element and spring element are applied to build the model entities and interfaces. The analysis result by FEM is consistent to the testing results. The research provides foundation for how setting up machining programs to avoid the resonance vibration of the machine in the operating.

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