bluuebunny/crossref_metadata_2025 huggingface dataset:
Flex Gradient Optimization on Stiffened Steel Plate of Profiled Plate Rubber Support
Authors: Yuan Duan Cai , Duan Jin Xi , Zhou Chu Shun , Meng Shang Yang
Published: March 2010

The plate rubber support is widely used in railroad bridge. To analyse its capability of transverse displacement resistance and increase its life-span, the finite element model of profiled plate rubber support is established by nonlinear finite element method. The influence of flex gradient of stiffened steel plate to the function of the plate rubber support is analyzed and the optimal gradient is obtained.The method and conclusions are available for designing of plate rubber support.
Constraint Reaction Forces and Lagrange Multipliers in Multi-Body Systems
Authors: Yao Wen Li , Ren Yong Sheng
Published: March 2010

The study performs the relation between the Lagrange multipliers and the constraint reaction forces in the multi-body systems. It helps to establish a simple and effective method to deal with the non-smooth factors including friction, contact and collision in multi-body systems. First, a general expression calculating the ideal constraint reaction forces is described by a form of complete Cartesian reference coordinate in a discrete dynamical system. Then, an explicit expression is given in the form of independent general generalized coordinates for a multi-body system. A condition under which the constraint reaction forces can be one-to-one corresponding to Lagrange multipliers is discussed. An example is used to demonstrate the process to realize the condition and the effectiveness of this method.
Simulation of Failure in the Refractory Lining of Coke Dry Quenching
Authors: Chen Xia , Chang Qing Ming
Published: March 2010

A model based on damaged mechanics is presented to analyze the failure behaviour of coke dry quenching refractory lining under circumstance of multifarious change of temperature by using finite element method. The refractory material behavior can be described by Drucker-Prager Plasticity model for compression and strain softening under tension. The simulation result is consistent with the experiment result. This paper provides a new method for the failure analysis of refractory material. The results can be used to optimize the lining design and the material selection.
Modeling Method of Crawler Crane Based on Open Source Engines
Authors: Wu Di , Zhang Jing , Gao Shun De , Wang Xin
Published: March 2010

Crawler cranes are the most expensive and frequently shared resource on construction sites, industries, etc. According to the characteristics of crawler crane, this paper presents a multiple modeling method of crawler crane based on OGRE (Object-oriented Graphics Rendering Engine) and Bullet Dynamic Engine. The multiple model is composed of rendering model, collision model, skeleton model and dynamic model. Based on this modeling method, not only vivid figuration and motion of the crane but also real-time collision detection and distance computation can be achieved.
A FEM Formulation for Flexible Multi-Body System Dynamic Analysis
Authors: Liu Jian , Ma Lv Zhou , Yan Yu Qin , Zhao Y.F.
Published: March 2010

A simple engineering language is used to present a geometrical non-linear formulation based on position description. Velocity, acceleration and strain are achieved directly from nodal position, not displacements. The proposed methodology is based on the minimum potential energy theorem. A non-dimensional space is created and the relative curvature and fibers length are calculated for both reference and deformed configurations and used to directly compute the strain energy at general points. Damping is introduced into the mechanical system by a rheonomic energy functional. The final formulation is shown simplifying the understanding and the implementation of large deflection analysis when compared with typical FEM formulations.
Study on Cost Minimization of Auto Engine Product Warranty Chain
Authors: Xie Qiu , Liu Zi Xian , Qui Er Shi
Published: March 2010

Aiming at how to optimize auto engine warranty cost, some hot issues such as what kind of factors auto engine warranty cost includes was studied deeply from the standpoint of reverse supply chain in this paper. First, the definition of auto engine warranty supply chain (AEWSC) was explained; then, under two-dimensional renewable free warranty policy, the components of AEWSC cost were analyzed for repairable engines. AEWSC cost covers not only traditional product warranty cost, but also potential cost resulting from re-failed engines; thirdly, an AEWSC Cost model was built based on cost analysis; finally, numeral analysis was developed through using the proposed cost model. The analysis results help engine manufacturer reduce AEWSC cost.
Fatigue Life Prediction of Isothermal Forging Dies Based on Average Strain Method
Authors: Cai Jun , Li Fu Guo , He Min , Chen Peng
Published: March 2010

Isothermal forging die plays an increasing important role in plastic forming. During isothermal forging process, die bears high and long-time thermomechanical loading, which leads to short service life and poor reliability. Therefore, estimating isothermal forging die life using traditional method will engender great errors. In this paper, an average strain of fatigue process zone in danger region is introduced to estimate service lifetime of isothermal forging die. An upper die of a Ti-4Al-6V disc is analyzed to investigate the service life of die. The result shows that using average strain method can estimate service life of isothermal forging die more exactly.
Pressure Pulsation Analysis of Aircraft Hydraulic Power Pipelines System
Authors: Liu Wei , Wei Tao , Yue Zhu Feng
Published: March 2010

The output pressure pulsation model for the aircraft hydraulic power pipelines was established by the methods of transfer function and fluid network chain-rules; the dissipation caused by frequency-dependent friction was taken into account. Dynamic characteristics of hydraulic system were discussed in frequency-domain and time-domain respectively, the pumping excitation frequency influenced the frequency-response of hydraulic pipeline system, and several resonance frequency bands were obtained. The inverse fast Fourier transform was applied to simulate the transient pressure pulsation waves under pump starting and steady-running state.
The Research on Milling Temperature and Heat Deformation of Tool in Virtual Numerical Control Simulation
Authors: Sui Xiu Lin , Jin Li Juan , Ge Jiang Hua , Zhang Jia Tai , Kong Zheng Wei
Published: March 2010

Joint modeling of exponentially fitting and least square method was proposed for key technical problems on milling temperature and heat deformation of tool in virtual numerical control (NC) simulation. Mathematic model of surface temperature and its influencing factors based on ball-end mill was established. Correlation coefficients of model are over 0.8, and the errors comparing with the experimental ones are within 10%, which shows that the model meets precision requirement, and fitting effect is good. By this model a mathematical model of the ball-milling cutter’s thermal deformation was established, and the relative error is small by comparing with test values, which proves that this model has high calculation precision and practical meaning. A simulation prediction system of milling temperature and ball-end mill’s heat deformation in virtual NC was developed based on above mentioned models, which can provide theoretical basis for machining error prediction, optimizing milling parameters and improving machining quality.
Study on the Formulas of the Dog-Bone Shape of Edger Rolling in Hot Strip Mill
Authors: Wang Ai Li , Yang Quan , Liu Hua Qiang , Du Xiao Zhong , Wang Xiao Chen
Published: March 2010

3D elastic-plastic FEM model was established with ANSYS/LS-DYNA for edger rolling in hot strip mill. The effect of width reduction of edger roll, the slab original width and thickness, and edger diameter on the main parameters of dog-bone shape has been studied. According to many simulated conditions, the formulas of the main parameters of the dog-bone shape have been developed. In order to test the accuracy of the models, multiple correlation coefficient and residual standard deviation were calculated.The results show that multiple correlation coefficients are all above 98% and residual standard deviations are all below 5%, which indicate that these formulas acquire a high precise.
Sticking Analysis of the Bistable Inductive Micro-Switch
Authors: Tian Wen Chao , Ren Huo Rong , Wang Liin Bin , Liu Huan Ling
Published: March 2010

Problems of the “false closure” and “instant closure” affect the antijamming capability and reliability of the micro-switch. Based on the sticking action, a new bistable micro-switch is put forward. A sine model is presented to describe the random distribution of the MEMS rough surface. Based on the sine rough model, the Casimir adhesion is simulated. The electric field force, which includes the edge effect, is discussed. Finally the threshold structure size is obtained, which can control the micro-switch to close stably and trigger automatically.
The Function Simulation of TBM Based on Virtual Reality
Authors: Li Gang , Wang Zhao Qian , Wang Wan Shan
Published: March 2010

Abstract. As we all known, it is a hard and risky task to use a real physical tunnel boring machine prototype in experiment for the reason that it is expensive, complex and used in an special operating environment. Based on virtual reality technology, the function simulation of digital mockup using VR system is proposed, the function simulation of full-face Tunnel Boring Machine (TBM) based on Division Mockup is finished and verified by the consistency between theoretical study and actual simulation results. This paper provides the basis for design and improvement of product in order to reduce the production costs and time-to-market.
Finite Element Analysis of Pressure Coiled Forming Process to Taper Weld Pipe
Authors: Tian Ya Qin , Chu Zhi Bing , Huang Qing Xue , Li Jin Bao , Qin Jian Ping
Published: March 2010

In order to reveal the deformation laws and characteristics of steel strips during the pressure coiled forming process, the stress-strain and contact force distribution of strips during the process were analyzed by the finite element ANSYS Software: the steel strips have strain along their length; strain ratios on both sides are slightly higher than that of the middle part; the equivalent force and the normal contact force in the strips are discrete distributed in the whole molding process. Compared with the corresponding experimental results, the macro experimental phenomena are basically consistent with the finite element numerical analysis rule, which provides the theoretical foundation and practical guidance for designing reasonable spiral pipe forming units.
Hot Deformation Behavior and Hot Processing Map of P92 Steel
Authors: Sun Shu Li , Zhang Min Gang , He Wen Wu
Published: March 2010

Hot-compression and hot-tension experiments were conducted on a Gleeble-1500D thermal-mechanical simulator. The constitutive equation was presented by calculating the stress exponent, activation energy and Zemer-Hollomon parameter during the hot compression. Based on dynamic material model theories and Prasad instability criterion, the hot processing map was developed and the representative microstructure was observed. The total elongation and reduction in area were calculated by the hot tension. These results have shown that P92 steel should be manufactured at higher processing temperature and larger strain rate in practice.
A Novel Multiple RBF-NN Model for Rolling Force Prediction Based on Anti-Aliasing Wavelet Analysis
Authors: Chen Zhi Ming , Cao Jian Zhong , Huang Jin Qiu
Published: March 2010

Aiming at the problem of rolling force prediction, an anti-aliasing wavelet method utilizing FFT and IFFT is first proposed to decompose the rolling force signal and reconstruct it as a serial of sub-components. Then several RBF networks, each with different input and output parameters, are established for the modeling of each sub-component, their output values are added up as the rolling force value. Simulation results show that this proposed model can reduce the system dimension, and improve the learning ability of the network. The error rate of rolling force prediction is reduced from 10% by BP-NN model to 4% by the proposed model.
Analysis of the Performance for a Group-Annulus Type Oil-Fired Boiler
Authors: Huang Hui Lan , Li Gang
Published: March 2010

To overcome the shortcomings of the traditional hot-water boilers, a oil-fired hot water boilers is improved design for a group-annulus structure. A finished product boiler is thermodynamic analyzed with the tested heat generation amount equivalent to 350 kW. The results indicate that the unique heat exchange structure of group-annulus type hot-water boilers can reduce thermal stresses and intensify convection heat exchange. The radiation heat-exchange space is 2 times more than that of the shell-tube boiler, and surfaces inside the furnace are comparatively large. Compared with shell-tube type boilers, the group-annulus type boilers is made a distinction with small volume and heat-exchange surface area, low metal consumption and high ratio of performance to cost under the same total heat-exchange quantity.
A Novel Boundary Extraction Algorithm on Triangular Meshes of STL Model
Authors: Peng Yu Hui , Gao Cheng Hui
Published: March 2010

The generation of boundaries from the triangular meshes of CAD object is very important for successful surface segmentation and subdivision. Considering the characteristics of non-uniformity, sparseness and known facet normal for STL model, which is generated by a CAD system, a new and efficient approach for extracting boundaries on STL model is presented in this paper. Boundaries are classified into sharp feature edge and non-sharp feature edge embedded in the filleting and transitive region. The former is detected based on dihedral edge angle (angle between facets), while the latter is identified by analyzing intrinsic region properties of triangular facets distribution without curvature estimation. By means of unidirectional increment of feature edges, continuous region boundaries are generated. Successful examples are presented to illustrate the feasibility of the proposed algorithm.
Automatic Solder Joint Defect Classification using the Log-Gabor Filter
Authors: Mar Nang Seng Siri , Fookes Clinton , Prasad K.D.V. Yarlagadda
Published: March 2010

This paper proposes the validity of a Gabor filter bank for feature extraction of solder joint images on Printed Circuit Boards (PCBs). A distance measure based on the Mahalanobis Cosine metric is also presented for classification of five different types of solder joints. From the experimental results, this methodology achieved high accuracy and a well generalised performance. This can be an effective method to reduce cost and improve quality in the production of PCBs in the manufacturing industry.
Study on Prediction of Machining Distortion for Titanium Alloy Aircraft Monolithic Component by FEM
Authors: Yang Yong , Li Hui Hui , Meng Guang Yao
Published: March 2010

A physics-based material processing simulation is approached to research the machining distortion for titanium alloy aircraft monolithic component by the finite element method (FEM). Several key technologies, such as material constitutive model, material removal methodology of machining process, determination and application of cutting loads, have been implemented to improve the accuracy of finite element simulation. To verify the FEM result, an experiment is carried out. The distortion position and dimension of aircraft monolithic component resulting from FEM show a good agreement with the experiment result, which indicates that the key technologies presented in the paper are practicable and can be used to simulate the machining process of monolithic component to predict its distortion.
Strip Profile Control in Asymmetrical Rolling by FEM Modeling
Authors: Du Xiao Zhong , Yang Quan , Jiang Zheng Yi , Zhang Xiao Ping , Wang Xiao Chen
Published: March 2010

Asymmetrical rolling is usually used on some special rolling produce. It offers lower rolling pressure, more reduction and better crystallographic textures. In recent years asymmetrical rolling has become more important due to realization of improved properties of the strip. In this paper, a elasto-plastic finite element method code has been developed to simulate the asymmetrical rolling of strip, considering unequal roll radii, unequal speed ratio between the upper roll and lower roll, different exit thickness and different reduction. Meanwhile, The profile, crown and edge drop of strip, as well distribution of front tensile stress were discussed in different rolling process. It makes better preset values for the online control system and good results was obtained.
Limit Pressure of Rupture Discs Found on Tensile Instability Condition
Authors: Gao Guang Fan , Wang Guo Dong , Ding Xin Wei , Chen Jiang Jun
Published: March 2010

With attention concentrated on the pole of bulge profile, tensile instability which results in the fracture of forward acting rupture discs has been studied. A formula was developed to calculate the theoretical limit pressure of rupture discs, and the theoretical predictions were compared with the measured data. It is found that the strain-hardening exponent of sheet metals has no influence on the limit pressure, whereas the limit pressure is in direct proportion to the strength coefficient of sheet metals. It is important to realize that the strength coefficient of sheet metals can be acquired easily from the limit pressure. This has potential value for the tests of mechanical properties of sheet metals.
A Framework of Cooperative Design for Aspheric Glass-Lens Mold
Authors: Zhu Yong Jian , Yin Shao Hui , Pan Wei Qing , Fan Yu Feng , Tang Kun
Published: March 2010

The lens molding technology has become a promising fabrication method for glass lens, especially for aspheric glass lens in batch. Because during the real compression molding, the error compensation for mold shape turns very difficult, the mold needs to be repaired repeatedly to meet the requirements of lens molding. To solve this problem, a cooperative design scheme is proposed. However, the scheme is not limited to solving the mold repairing; it also aims to providing the integrated and optimal design for aspheric glass-lens mold. In fact, the cooperative scheme is a collaborative software platform, which integrates with data processing, optical design, finite element analysis, error compensation and mechanical design for lens molding. On this platform, users only need to submit the (camera) lens parameters or measured data of aspheric lens, and then the platform can provide the final mold drawings, which will be input in the CNC software of ultra-precision machine and guide the mold fabrication. Meanwhile, the cooperative platform is Network-based PDM system, so designers could remotely communicate with it and help to finish the mold design jointly. In this case, the cooperative design could tremendously improve the efficiency and accuracy of lens molding.
Prediction and Prevention of Overburning Structure during Hot Processing of Chromium Forged Steel
Authors: Li Shun Jie , Peng Kun , Yang Yi Tao , Shao Guang Jie
Published: March 2010

The critical overburning temperature of chromium forged steel was experimented and discussed by DSC method and metallographic analysis of heat-treatment samples. Temperature increase during forging process and effects of some alloying elements on overburning temperature were simulated respectively by using Deform-3D and Thermo-calc software. The results of linear regression analysis showed that increased temperature has a prop relationship between volume and rate of forging process. Besides, a monotonic decreasing relationship is found between the content of alloying elements with overburning temperature in the scope of the composition of chromium forged steel. It is found that carbon has the major effect on the overburning temperature.
Analytic Modeling of Rolling Force during the Hot Rod Rolling of Multiple Alloying Steels
Authors: Yang Lei , He Yi Zhu , Zhang Hui , He Yin Sheng , Shin Kee Sam
Published: March 2010

This paper proposes a semi-analytical method for the prediction of rolling force for rod rolling. The grooves of the passes are oval-round and round-oval. The mathematical model of rolling force is based on Shinkura and Takai’s model, but incorporates the effects of recrystallization and the alloy elements. Hot rod rolling experiments are conducted to examine the proposed semi-analytical method. The predicting values are compared with the mill log data, and they agree excellently over the whole rolling course. The predictions indicate that recrystallization affects the resistance of the material during hot rod rolling.
Simulation of Thermal Deformation for Spindle of Machine Tool
Authors: Chang Chia Lung , Wang Yung Cheng , Wang Yi Chieh , Lee Bean Yin
Published: March 2010

In order to increase the efficiency of machine tools, the development of machine tools is toward higher speed and accuracy. The higher speed of spindle causes more thermal deformation, which reduces the accuracy of machine tools. In this study, finite element method is used to simulate the thermal deformation of spindle caused by the friction loads between spindle and bearings. The bearing load is estimated by the basic load rating from the bearing vendor and the required life of bearing. The simulated results are compared with experimental measurements to verify the analysis model. The result shows that the stabilized temperature of spindle increases as the speed increaser, while the stabilized displacement of spindle slightly increases as the speed increases.
Nonlinear Numerical Optimization Design Applied to Wall-Thickness of Welding T Shaped Connecting HDPE Tube
Authors: Guo Yong Chang , Deng Jun , Xie Hao Bin
Published: March 2010

There are two reasons to enlarge the thickness of welding HDPE tri-branch tube. Firstly, welding weakens the HDPE material properties. Secondly, stress concentration occurs at the joint of tri-branch tube. The material properties of HDPE and the tensile strength of welding HDPE were tested. Based on the test results, the wall-thickness of HDPE tri-branch tube was investigated by numerical optimization design with particle swarm optimization (PSO). Two material constitutive models of elasto-palstic and Ramberg-Osgood for HDPE are adopted in FEM. Some valuable conclusions of pipeline design are concluded by the distribution of stress contour curves and optimization curves of welding joint of HDPE tri-branch tube.
A Parallel Numerical Study of Transient Heat Transfer and Fluid Flow of Weld Pool during Laser Keyhole Welding
Authors: Pang Sheng Yong , Chen Li Liang , Yin Ya Jun , Duan Ai Qin , Zhou Jian Xin , Hu Lun Ji
Published: March 2010

Numerical simulation provides a way to improve our understandings of the heat transfer and fluid flow behaviors of the weld pool during laser keyhole welding. However, current numerical studies are only limited to serial simulations which running on a single CPU. In this study, a parallel numerical study of the heat transfer and fluid flow of the weld pool is presented. A mathematical model considering the effect of Marangoni force, buoyancy force, friction force of the mushy zone region and the effect of keyhole is presented. A combined keyhole volume and surface heat source model is also developed. The coupled transient heat transfer and Navier-stokes equations are solved with a high order accuracy parallel projection method. The simulation code is parallelized with the OpenMP language. It is shown that 200% speedup can be achieved on a shared memory quad-core CPU using the presented parallel simulation system. The simulation results agree well with the in-situ high speed CCD video imaging experiments and the literature results.
Temperature and Stress Analysis in Micro-Cutting of Ti-6Al-4V and Al7050-T6
Authors: Lu Dong , Qin Guo Hua , Wang Cong Kang , Rong Yi Ming
Published: March 2010

A finite element method (FEM) for predicting the temperature and stress distribution is presented. Two workpiece materials were carried out, one is Al7050-T6 the other is Ti-6Al-4V. The flow stress of workpiece material is taken as a function of strain, strain rate and temperature in order to reflect realistic behavior in machining process. Diamond cutting tool with rake angle 50, clearance angle 100, and cutting edge radius 1 is used. From simulation, cutting force, thrust force, and distribution of cutting temperature and stress are obtained.
Research on Machining Simulation System for Optical Free-Form Surfaces
Authors: Hu Yong , Xu Ming Xu , Zhang Jun , Mao Bo , Zhou Xiao Qin
Published: March 2010

This paper presents a new simulation system for ultra-precision diamond turning of optical free-form surfaces based on fast tool servo (FTS). The functions including evaluation and analysis of optical free-form surfaces manufacturing errors, optimization for tool path, etc, are proposed. The simulation modules and functional structure of the system are designed in accordance with the functions. The errors in the process of machining can be found in advance through the simulation. Then the NC code will be modified timely. The proposed method can be used to improve product quality, shorten the development cycle, reduce costs and optimize machining process.
Simulation of Aluminium Foam Compressive Properties
Authors: Zhao Ming Juan , Zhao Long Zhi , Li De Ying , Zuo Xiao Qing , Lu Jian Sheng
Published: March 2010

In this paper, the simulation of the commpress properties of Al foam was investigated by finite element methods. The simulation results show that the compressive yield strength of Al foam is consistent with the theoretical model of Gibson and Ashby. The yield strength of Al foam decrease with the increase of porosity, and the yield strength decreases significantly with the increase of porosity. The density of Al foam is proportional to the compressive strength. At a certain porosity, the ratio of sample size and the aperture have an extremely important effects on compressive behavior of aluminum foam. When 4 ≤ D / d <8, with the increase of the ratio of D / d, the plastic deformation plateau and the compressive strength of metal foam is increasing ; on the contrary ,when the ratio> 8, with the increase of the ratio, the plastic deformation plateau is decreasing, the compressive strength keeps constant.
An Integration-Based Stochastic Finite Element Method
Authors: Gao Xiao Ke , Deng Zi Chen , Li Wen Cheng
Published: March 2010

A straightforward numerical method for the computation of response of non-linear finite element system with uncertain parameters under stochastic loading is presented. This method is based on the special form of the probability destiny function of the random variables and, in particular, on the Gauss-Hermite integration rules to compute the response. In the method, a direct and simple formulation, which can just be signed as a symbol of function, is given to represent the relationships between random response and the randomness of the system parameters. In this way, it becomes much easier to obtain the response quantities by computing the double integrals, in which the stochastic parameter of the finite element system is considered as one of the integration variables in the computational procedure, as well as the external force with random characteristic. An example shows the performance of the method.
Investigation of the Relationships between Billet Reheating and Semi-Solid Die-Casting
Authors: Yin Xiang Lin , Yang Yi Tao , Shao Yu Peng , Shao Guang Jie
Published: March 2010

The non-dendritic of A356 aluminum alloy billet was reheated to meet the requirements of the semi-solid microstructure by three different kinds of power, achieving the same final temperature of 863K. Subsequently, under the same conditions of die-casting (thixoforming), the microstructure was observed, surface hardness and tensile properties were measured. Afterwards, quantitative analysis was made for the microstructure of the reheated semi-solid of billet and the thixoforming parts. The results showed that the larger induction reheating power of the billet, the smaller the grain size of its microstructure and the higher surface hardness and the better mechanical properties of its thixoforming sample. Finally, through studying on the relationship between the microstructure of the semi-solid billet of A356 aluminum alloy and the mechanical properties of the thixoforming sample, we primarily achieved the reverse design of microstructure.
Analysis of Transverse Wall Thickness Precision of Steel Tube Rolled by Semi-Floating Mandrel Mill
Authors: Yin Yuan De , Li Sheng Zhi , Xu Jie , Li Yang Hua , Long Gong Ming , Deng Pi An
Published: March 2010

With the aid of commercial finite element analysis software MSC. Superform, the high pressure boiler steel tube continuous rolling process with 6-stand semi-floating mandrel is simulated, and the distribution characteristic of transverse wall thickness is analyzed. It indicates that it presents “M” shape that the distribution of transverse wall thickness of hollow tube along one-fourth groove periphery. Transverse wall thicknesses have low values at the top, the bottom and sidewall 45 degree or so of groove, and they have high values at the sidewall 23 degree and 67 degree or so of groove. Then the improved measure is put forward on the basis of analyzing the causes responsible for transverse wall thickness. By the comparison of the simulation results, they have been improved obviously that transverse wall thickness precision and real roundness of rolled hollow tube using the improved measure.
A Model of Cutting Forces for Ball End Mill in High Speed Machining
Authors: Yan Bing , Xu Chao Hui , Wang Wei
Published: March 2010

The machining characteristics of hardened still for mould and die greatly affect the accuracy and productivity in industry. The physical modeling and simulation of ball end milling is investigated in this paper. The influence of cutting speed to the cutting mechanism in high speed cutting is taken into account and the momentum force of chip is introduced into the model. By analyzing the shape of the chips the relationship between the cutting speed and shear angle is obtained. The model has been tested on 718HH, with appropriate Seco tools. The validation shows that the adjustment between the model and the real force is adequate, both in shape and magnitude.
Numerical Simulation of ANSYS-LS/DYNA Induced by Double-Edge Ball Tooth Hob Cutter
Authors: Tan Qing , Wang Kai , Xia Yi Min , Zhang Kui , Xu Zi Jun
Published: March 2010

In order to analyse the rock breakage process of double-edge ball tooth hob cutter and get the related curve of intrusive force and invasion depth, the numerical simulation model of double-edge ball tooth hob cutter is accurately established. In the process of interaction between hob cutter and rock mass, the material model is also established, the mechanism of rock fragmentation is carefully researched, the elastic-plastic deformation is seriously studied. Finally, we design an experiment which has a good consistency with the simulation analysis.
Research on Interpolation Algorithm of Three-Links Hybrid Machine Tool
Authors: Zhu Li Da , Li Gang , Wang Wan Shan
Published: March 2010

Aiming at the characteristics of structure and control of three-links hybrid machine tool, the interpolation strategy of CNC system is proposed in this paper. Coarse interpolation in workspace and fine interpolation in joint-space are expatiated. The trajectory points are transformed into discrete points by coarse interpolation mapping from workspace to joint-space. At the same time, the plans of trajectory, velocity and acceleration of discrete points in workspace are got, and then joint discrete points are realized by joint fitting smooth function. In order to meet the design demand and enhance effectively interpolation precision, the five polynomial interpolations will be thinning discrete points, and geometric locus will be very smooth.
A Method for Performance Evaluation of Transfer Line with Unreliable Machines and Finite Transfer-Delay Buffers
Authors: Xia Bei Xin , Xi Li Feng , Zhou Bing Hai
Published: March 2010

Performance evaluation techniques of manufacturing systems are powerful decision support tools especially at system design stage. In this paper, an approximate technique based on decomposition method is proposed for performance evaluation of serial homogeneous transfer lines with unreliable machines and finite transfer-delay buffers. The characteristic of transfer-delay buffers means that it takes some transit time to transfer the parts through buffers, which increases the complexity of transfer lines. In order to address the problem, we firstly transform the initial transfer line into an equivalent transfer line, a serial non-homogeneous transfer line with unreliable machines and finite buffers. Then another transformation which replaces the equivalent line by an approximate homogeneous line is introduced. Finally, decomposition method is used to deal with the approximate model. The accuracy and efficiency of the method are validated by simulation results.
Closed-Loop Identification and Composed Controller Design for Precise Machining
Authors: Sheng Jun , Li Jian Gang , Zhou Lei
Published: March 2010

For a class of three-loop architecture motion control system, two-stage close-loop identification is introduced to estimate the control plant and thus to tune the velocity controller. Based on the estimated model, PID position controller with derivative filter is proposed using pole-zero cancellation and pole assignment. Feed-forward compensators such as Velocity and Acceleration Feed-forward Controller (VAFC), Zero Phase Error Tracking Controller (ZPETC), Zero Magnitude Error Tracking controller (ZMETC) are introduced as well, and their effects are compared.
The Process Planning Simulation of Multi-Axis Numerical Control Based on Virtual Reality
Authors: Luo Lu Feng , Sun Shuang , Meng Qing Guo , Li Quo Qing
Published: March 2010

In view of the limitation of trial cutting or manual inspection of the process planning validation of conventional numerical control, a new method of planning process simulation based on virtual reality was proposed. Firstly, the structure and implementation scheme of simulation system were given, and the simulation platform was established. Then, the movement behavior of machine tool was analyzed in details, an event handle model based on message response mechanism was proposed. Take tool change for example, the behavior module and the motion mode of related components were described. Researched and inferred the solving process of the curved surface of tool sweeping. The NC code compiler and cutting process simulation were expounded. Finally, the system was realized by means of using Visual C++6.0, OpenGL, Virtools and so on, It could verify the rationality of process planning and achieve the accurate assess.
Numerical Analysis and Optimization of Stamping Technology for Electrical Motor’s Cover
Authors: Liu Bai , Zhou Yong Quan , Liu Ming Jun , Zhao Zhen Yu
Published: March 2010

Based on Finite Element Analysis (FEA) module of Dynaform software, the paper made numerical simulation of a motor cover’s stamping process in the method of elastic-plastic flow, pointed out the behavior of deformation of stamping process, predicted and prevented stamping defect such as crack in the process, and calculated the degree of resilience. Consequently three forming numerical simulation schemes have been designed respectively, more feasible process parameters has been achieved in comparison with the features of each scheme.
Redesign of a Complicated Component of Auto Body Based on the Properties of TWBs
Authors: Ning Yu , Han Ying Chun , Wang Chun Yan
Published: March 2010

With a synthetic study on the mechanical properties and deformability of TWBs, and an advanced mechanical analysis of weld-line movement, the theoretic basis for the whole forming and redesign of a complicated component of auto body (body side-inner panel) was achieved. Then a preliminary redesign was conducted with the selection and collocation of parent metal, the layout of the welding position, and the design of integral forming drawing taken into consideration. Thereafter, by simulation forming and parametric optimization, the redesign of the component was completed and its stamping forming technology was greatly improved.
The Strength Design and Check of Turbine Generator Based on FEA and Fatigue Evaluation
Authors: Liu Chao , Jiang Dong Xiang , Hong Liang You
Published: March 2010

As the capacity and thermal parameters of turbine generator become larger and higher, the strength design plays increasingly important part in manufacturing process while the traditional strength check method based on the nominal stress which is modified by the stress concentration factor has many disadvantages. The paper proposed Finite Element Analysis (FEA) to analyze the local stress which is more accurate and convenient to seek the dangerous failure point. The possible running conditions which maybe encountered in field are needed to be adequately considered in design process. Two phase short circuit which is the unavoidable condition in the unit’s running porcess plays significant impact on the shafts strength life and the unit’s life-cycle. The paper analyzes the fatigue evaluation of two phase short circuit to enhance the design reasonability as a typical case study. Using FEA and fatigue evaluation methods, more details of the shafts structures and the running processes are taken into accounts which make the dseign process more reliable.
Multi-Field Co-Simulation Research on Suspension System of Forging Manipulator Based on Virtual Prototype Technology
Authors: Zhai Fu Gang , Kong Xiang Dong , Ai Chao , Liu Jie
Published: March 2010

Take a certain suspension system of forging manipulator as research object, mechanical system sub-model and hydraulic control system sub-model of suspension system were respectively built by using Pro/E, Mechanism/Pro, ADAMS and AMESim software, and the whole virtual prototype model of suspension system contains mechanical and hydraulic system sub-model was connected by interface module of software collaboration. Based on integrated features of virtual prototype technology, the dynamic and static characteristics of suspension system were researched by the method of multi-field co-simulation and software collaboration. The results can provide certain theoretical significance for designing suspension system of forging manipulator.
FE Analysis of the Effects of Cutting Speed on Thermomechanical Responses of AISI 4142 Steel in High Speed Cutting
Authors: Gao C.Y. , Fang B.
Published: March 2010

The high-speed metal cutting process is analyzed by finite element (FE) method in order to understand the effects of the cutting speed on the thermomechanical responses of workpiece materials. The reliability of numerical simulation is firstly validated by comparing the simulated cutting force with experimental data. Then a series of FE simulations are carried out to reveal the effects of the cutting speed on three key cutting state variables. The cutting force varies with the cutting speed and shows a minimum inflexion at 10 m/s. The maximum temperature in the secondary deformation zone increases gradually with the cutting speed and finally tends to a steady value. The residual stress decreases with the cutting speed as a whole. Thus high speed cutting can improve surface machining precision of product. Besides, it is found that the high residual stress mainly concentrates in the topmost surface layer with a depth of 0.1 mm and sharply decreases to a low level beyond the layer.
Exact Optimization of Time, Cost and Quality in Manufacturing
Authors: Hong Li , Yu Jian Jun , Sun Shu Dong
Published: March 2010

Time, cost and quality are three central objectives the manufacturing enterprises seek, but they restrict and affect each other. To analyze the relations among three objectives and achieve their exact optimization during manufacturing are the important problems which are worth researching. Based on the practice investigation and reasoning, the action mechanisms of three objectives are deeply analyzed, and their effect rules and relations are ascertained. The optimization model of time-cost-quality is set up according to their relations. The special program is designed for the integrative optimization model based on the idea of accurate calculation, and is applied to solve the optimization problem. Finally the methods put forward are applied to the instance about car part manufacturing, and a series of optimization result is obtained. Some conclusions which are valuable for the manager in enterprise are summarized by analyzing the optimization result. The instance application indicates that the model and the methods can help to make decision for production.
Research on the Connecting Performances of 1/10 Taper Spindle / Tool-Holder for High-Speed NC Machine
Authors: Zhou Qin Yuan , Zhou Zhi Xiong
Published: March 2010

Under the circumstances of 7/24 taper tooling system being widely replaced by 1/10 taper tooling system in the high-speed machining, using 1/10 taper HSK- A63 tools as the research object, this article, adopting the method of finite element method, analyzes the parameters such as clamp force, surplus magnitude and rotary speed which affect the connecting performances of 1/10 taper spindle/ tool-holder. The results of this study provide basic and useful guidance for the parameters’ selection of 1/10 taper tooling system in practical machining.
The Comparison Research of Two Working Electrodes in Electrochemical Reduction of Silicon Tetrachloride
Authors: Liu Wen , Ma Qiu Ping , Guo Jing Yan , Wang Bao Cheng , Meng Qing Sen
Published: March 2010

Silicon was electrodeposited by electrochemical reduction of silicon tetrachloride in propylene carbonate solvent on an alloy of nickel-titanium-niobium and nickel, which were used as working electrodes respectively. The effect of two substrates as working electrodes on the electrodeposition ability of the silicon was investigated by scanning electron microscopy (SEM) and energy dispersion spectroscopy (EDS). Results show that using an alloy of titanium, nickel and niobium as working electrode is better than nickel in the morphology and deposition yield of silicon.
Thermal Error Robust Modeling and Real Time Compensation Based on the GA-BPN Theory on a Vertical Machine Centre
Authors: Wang Xiu Shan , Li Yan , Yu Yong Chang
Published: March 2010

Thermal errors generally account for as much as 70% of the total errors of CNC machine tools, are the most contributor to the workpiece dimensional precision in precision machining process. Thermal error compensation is an effective way to decreasing thermal errors. Precision mode is a key to thermal error compensation. In this paper thermal error modeling method based on the artificial neural networks (ANN) algorithm is applied for a vertical machining center. Four key temperature points of a vertical machining center were obtained based on the temperature field analysis. A novel genetic algorism-Back propagation neural network (GA-BPN) thermal error model was proposed on the basis of four temperature points. The emulations and experiments prove that there was about a 60% increase in machine tool precision.
Structural Optimization of Non-Contact Vortex Negative Pressure Carrier
Authors: Ma Wen Qi , Xu Li Fang , Yu He Chun
Published: March 2010

Simulation models based on the different structural levitation vortexes were built, the analysis on the flow characteristics of pressure distribution and bearing capacity was conducted by using the RNG κ-ε turbulent model and non-uniform meshing in variable working conditions. At last, the influence factors and variation rules of vortex adsorption negative pressure effect were obtained. The theory and the experiment results indicate that the vortex carrier with symmetrical tangential air supply has the optimal stability, but the optimal negative pressure effect and the great lifting force are obtained by the vortex carrier with tangential single air supply.
A Hybrid Approach of ANN and HMM for Cutting Chatter Monitoring
Authors: Zhang Chun Liang , Yue Xia , Jiang Yong Tao , Zheng Wei
Published: March 2010

The Hidden Markov Model (HMM) offers a powerful framework for temporal modeling of features extracted from time varying signals, and the Artificial Neural Network (ANN) has been widely used for pattern recognition, time series prediction, and optimization and forecasting. This paper describes a hybrid HMM/ANN approach which is a very competitive alternative to standard HMM for cutting chatter monitoring both in terms of performances and recognition accuracy. The hybrid HMM/ANN system uses ANN, usually a Multi-layer Perceptron ANN, to integrate the multi-stream inputs as feature transformation, whose goal is to take the advantages from the properties of both HMM and ANN. Experimental results show the efficiency of the hybrid system in monitoring of cutting process.
State Monitoring for Centrifugal Pump of PWR Based on HMM and SVM
Authors: Zhang Chun Liang , Li Sheng , Yue Xia
Published: March 2010

The centrifugal pump of pressurized water reactor (PWR) in nuclear power plant is characterized by its complicated system, small accumulated data and fault samples. HMM has a strong ability to deal with time series modeling for dynamic process, while SVM has excellent generalization ability to solve the learning problems with small samples. This paper develops a state monitoring system based on the hybrid HMM/SVM model. The wavelet analysis techniques are used to extract features and the Hidden Markov Model (HMM) and Support Vector Machine (SVM) are used as the basic modeling and identification tools. The identification results of centrifugal pump show that the hybrid HMM/SVM system is effective and available for the state monitoring of the centrifugal pump of PWR in nuclear power plan.
Microstructure and Mechanical Properties of Heavy Gauge Plate by Vacuum Cladding Rolling
Authors: Xie Guang Ming , Luo Zong An , Wang Hong Guang , Wang Guo Dong , Wang Li Jun
Published: March 2010

The cladding steel plate was successfully produced using vacuum cladding rolling method. In cladding steel plate, cladding interface vanished and was replaced new recrystallized grains, and no interface defects or inclusions were detected. Z direction tensile testing indicated that tensile fracture occurred in basal materials, i.e. strength and contraction of cross area are those of basal materials. Furthermore, with decreasing vacuum level of electron beam welding, size and amount of interface inclusions would obviously increase.
A Particle Swarm Algorithm for Assembly Sequence Planning
Authors: Xing Yan Feng , Wang Yan Song , Zhao Xiao Yu
Published: March 2010

A particle swarm algorithm is proposed to generate optimal assembly sequences for compliant assemblies. Firstly, the liaison graph and the adjacency matrix describe the geometry of the compliant assemblies. An assembly sequence is represented by a character string, whose length is the number of all parts. The conceptual tolerance analysis is used to evaluate feasible sequences. Thereafter, the particle swarm algorithm is presented to generate assembly sequences, in which the elite ratio is applied to improve optimization results. Finally a fender assembly is used to illustrate the algorithm of assembly sequence generation and optimization.