bluuebunny/crossref_metadata_2025 huggingface dataset:
Innovative Method of Shielding the SS Pipe Carrying Industrial Wastes by Using Self-Compacting Concrete for Sustainable Construction
Authors: Sivathanu Pillai C. , Santhakumar A.R. , Murugan R.
Published: May 2016

In an underground R.C. Tunnel constructed as conduit for SS Pipes carrying industrial waste liquid, heavy ingress of ground water was witnessed and had to be overcome. Industrial wastes are to be carried through pipes in pipe system with an outer casing of a 200 mm dia SS pipe. Continuous contact of ground water with the casing SS pipe will deteriorate the pipe with the consequence of mixing of waste with the ground water. To avoid this, tunnel was sealed by enclosing the casing pipe with self-compacting concrete (SCC) for preventing ingress of ground water into the tunnel. As sustainability comprise Economy, Environment and social impact, the use of SCC take care the above factors by utilizing fly ash which replaces cement ,thereby, protecting the environment from industrial waste to produce socially accepted concrete and ensuring sustainable construction.
Experimental Study on the Wear of Single Crystal Diamond Tools in Ultra-Precision Cutting of Titanium Alloy
Authors: Hu Lin Hua , Zhou Ming
Published: May 2016

In this paper, ultra-precision cutting experiments were carried out with titanium alloy material Ti-6A1-4V by using single crystalline diamond tools. Experimental results show that the wear patterns of rake face of diamond tools are crater wear and groove wear, the wear patterns of flank face of diamond tools are uniform wear and groove wear, and the wear mechanisms of single crystalline diamond tool are chemical wear and mechanical wear. Graphitization and microcosmic cleavage of the diamond tools occur in the cutting process.
Research on the Finite Element Simulation of the Laser Shock Forming of TC4 Titanium Alloy
Authors: Li Guo He , Mbukwa David , Zhao Wei
Published: May 2016

laser shock forming, which combines the metal forming and material modification, is a non-mode, flexible forming new technology using laser-induced force effect of high amplitude shock waves to obtain the plastic deformation of sheet metal. in this paper, the simulation of laser shock forming process of tc4 sheet metal was carried out through the commercial finite element analysis software abaqus. the influence of the sheet thickness, laser energy, constraints aperture and laser spot spacing on the sheet metal deformation are investigated. the results show that: with the increase of sheet thickness, the deformation range of sheet decreases, and the amplitude of deformation decreases firstly and then increases. the deformation increases linearly with the increase of laser energy. the larger boundary constraint aperture leads to the larger deformation of sheet metal. there are no obvious influence on the forming accuracy when an opposite laser spot spacing is adopted. therefore, under the condition of meeting the accuracy requirement, for improving the efficiency, adopting a certain laser spot spacing to finish the forming should be considered.
A Fault Diagnosis System Based on Bistable Stochastic Resonance and Dynamic Time Warping
Authors: Liu Zhen Wu , Shang Zhi Wu , Li Ya Feng , Wang Tai Yong
Published: May 2016

Stator current signal of driving motor can be easily measured. Using it in the gearbox fault diagnosis system is inexpensive and suitable for remote monitoring. According to the application of the Motor Current Signal Analysis in machinery fault detection, we present a new gearbox fault diagnosis system. In modern signal processing technology, Stochastic Resonance theory is widely used to improve SNR (signal to noise ratio). Dynamic time warping algorithm is a simple and efficient way of the pattern identified. Combine the Stochastic Resonance theory and dynamic time warping algorithm as the basic theory of fault diagnosis. To realize the development of fault diagnosis software, we use the mixed-programming of MATLAB algorithms library and VC++.
An Edge Detection Algorithm Based on Edge-Preserving
Authors: Tang C.R. , Li A.
Published: May 2016

The traditional first-order differential operator is under the influence of the Gaussian noise, therefore, it often implement boundary extraction after average filtering. But the filtering process would often smooth the details of some directions of image too much, so that the edge cannot be extracted correctly. To solve this problem, this paper puts forward the edge detection algorithm based on edges keep, to determine the keeping direction of the edge through matching different directions’ edge template. Instead of average filtering process, it can improve the performance of traditional operator, and provide the simulation results. Experimental results show that the algorithm can eliminate noise, and at the same time, keep more edge information of the image.
Five-Axis Stone Carving Machine Modeling and Optimization Design of the Column
Authors: Tian Wei , Tian Ying , Zhang Lei , Song Zhi Hui , Sun Jian
Published: May 2016

Basing on the combining of the stone carving technology and the traditional machining technology, some parts of the design of five-axis linkage machine tool has been done and the virtual prototyping of the machine tool has been finished. This paper focuses on the whole structure’s modal analysis and column’s structural optimization of the five-axis machine tool. In view of normal surface with a large length to width ratio, we can optimize the wall thickness of the column to ensure a better dynamic performance. In the process, when the wall thickness is 10mm, the result shows a reasonable modal frequency and fitting weight.
Blind Source Separation for Under-Determined Mixtures Based on Time-Frequency Analysis
Authors: Li Hong Kun , Liu Hong Yi , He Chang Bo
Published: May 2016

Blind source separation (BSS) is an effective method for the fault diagnosis and classification of mixture signals with multiple vibration sources. The traditional BSS algorithm is applicable to the number of observed signals is no less to the source signals. But BSS performance is limit for the under-determined condition that the number of observed signals is less than source signals. In this research, we provide an under-determined BSS method based on the advantage of time-frequency analysis and empirical mode decomposition (EMD). It is suitable for weak feature extraction and pattern recognition. Firstly, vibration signal is decomposed by using EMD. The number of source signals are estimated and the optimal observed signals are selected according to the EMD. Then, the vibration signal and the optimal observed signals are used to construct the multi-channel observed signals. In the end, BSS based on time-frequency analysis are used to the constructed signals. Gearbox signals are used to verify the effectiveness of this method.
Composite Fault Diagnosis and Intelligent Maintenance Based on Data Driven
Authors: Liu Jing , Dong Yong Feng , Li Yan , Lei Si Yuan , He Shu Qun
Published: May 2016

For composite fault is difficult to diagnose, the characteristics of the large amount of data. This paper presents a method of The Prediction method of Composite Fault Based on data driven to establish intelligence unit Based on a collection of virtual individuals associated with the virtual failure associated collection and virtual behavior associated collection. Composite fault warning engine modeling is proposed, and give the warning value of composite fault finally. This method is fully assessing the future "dominant state" on the basis of the fully aware of current "hidden state". The impact of factors such as disturbance of hidden failures on composite fault prediction are fully considered, to some extent, the long-span composite failure prediction problem is solved, and the experiments show that the method effectively increases the accuracy of composite fault prediction.
Research and Simulation of SVPWM Algorithm Based on BP Neural Network
Authors: Ji Hua , Li Zhi Yong
Published: May 2016

In this paper, a space vector PWM (SVPWM) control algorithm based on BP neural network is proposed to cope with the complex calculation required in SVPWM through analyzing SVPWM for three phase voltage fed inverter. This method uses the strong nonlinear approximation ability of the BP neural network to fit the eqivalent segment SVPWM modulated wave, modulate with the triangular carrier wave, and then get the control signals of the three phase voltage inverter. A simulation model for PMSM control system was developed by MATLAB/Simulink with the neural network Toolbox. The results show that the BP neural network based SVPWM algorithm makes the motor control system has a smaller current harmonics and torque ripple, and reduce the amount of computation in digital control system with strong guidance.
Research on SVM Based Diagnosis System for Oil Tubing
Authors: Jing Lu Yang , Chen Dong Xiang , Wang Tai Yong , Wang Peng
Published: May 2016

Oil tubing is one of the most used equipment in oil extraction operations. An effective diagnosis system for it can provide multifarious benefits such as improved safety, efficient production and reduced costs for maintenance. In this paper, a support vector machine (SVM) based diagnosis system for oil tubing is studied and designed. SVM method has many advantages in solving the problem of small sample, pattern recognition of high dimensionality and nonlinear problems, which is fitable to the situation of oil tubing diagnosis. The SVM based diagnosis system for oil tubing is consisted of two parts: The hardware system part, including the detector and conditioning circuit board, and the software system part, including the SVM based analysis system. The detector is disposed on the wellhead and detects the leakage of magnetic field. The conditioning circuit board focuses on signal amplification and noise removal. The SVM based analysis system diagnoses the faults by the features of detected signal. An experiment platform is designed to certify the whole system and prove it perform well with a high diagnosis accuracy.
Signal Classification for Pipeline Security Threat Event Based on Optimized Support Vector Machine
Authors: Tan Dong Jie , Zhang Hong , Liu Lu
Published: May 2016

The way of efficiently classifying the manual digging, machine excavation, vehicle passing and other pipeline security threats, is an imperative problem for optical fiber pipeline security warning system. To solve this problem, a security threats classification method based on optimized support vector machine is proposed. In this method, after feature extraction based on wavelet to the original vibration signal, the artificial bee colony algorithm is introduced to optimize the penalty factor and kernel parameter of support vector machine under specified fitness function, and the optimized support vector machine is used to classify the pipeline security threats. To testify the performance of the proposed method, the experiment based on UCI feature datasets and actual vibration signal are made. Comparing with the support vector machine optimized by other algorithms, higher classification accuracy and less time consumption is achieved by the proposed method. Therefore, the effectiveness and the engineering application value of this proposed method is testified.
State Inspection and Fault Diagnosis System of Train Axel Box Bearing Based on Virtual Instrument
Authors: Wang Peng , Zhang Pan , Jing Lu Yang , Liu Zhe
Published: May 2016

Fault diagnosis of train bearing is an important method to ensure the security of railway. In the paper, four time domain statistical analysis methods and resonance demodulation method as a frequency domain analysis method are introduced. A state inspection and fault diagnosis system of train axel box bearing is constructed and its efficiency is also tested by wheel set experiment.
Study on the Influence of Roughness on the Detection for Mechanical Characteristics of the Machined Surface by Surface Acoustic Wave Dispersion Theory
Authors: Xu Jing Lei , Lin Bin , Wei Ya Xu
Published: May 2016

The surface acoustic wave (SAW) technique is a precise and nondestructive method to detect the mechanical characteristics of the precision-machined surface. The paper is concerned with the effect of the roughness of the machined surface on the dispersion of surface acoustic waves propagating in the precision-machined surface which indicates mechanical characteristics of the machined surface. The finite element method (FEM) is employed by establishing a series of models with different roughness Ra value to analyze influences from different roughness Ra value on surface acoustic wave dispersion. The models are established by applying a combined method based on fractal theory and wavelet analysis. The simulation results showed that the roughness of machined surface will cause the dispersion of surface acoustic wave propagation, the effect varies with the different roughness Ra values. A critical Ra value influencing on the surface acoustic wave propagation exists. Accordingly, that the factor of roughness should be considered in advance or not, the situation can be determined through studying and determining the critical roughness Ra value above mentioned. Consequently, the study has the important meaning regarding the detection for mechanical characteristics of the machined surface.
Weak-Points Diagnosis and Optimization of Shield Machine Cutter Tool Based on Characteristic Parameters
Authors: Zhao Jian , Hong Xue Wu , Yu Ming , Gao Zhi Peng , Wang Wen Jin
Published: May 2016

Shield machine plays an indispensable role in the mining, transportation, underground engineering, hydraulic engineering and municipal construction. Shield cutters of shield construction process often appears serious deformation, damage that leads to engineering accident, or even a threat to human life and safety. In order to provide high precise data for shield machine cutter tool dynamic modification and to diagnose the shield machine cutter tool fault, the dynamic characteristic of the shield machine cutter tool system, which is the main component of a shield machine cutter tool, has to be obtained precisely. The compute modal parameters identification method base on the finite element method is proposed to identify the modal parameters of the shield machine cutter tool. By means of Solidwords software, the knife ring structure of the shield machine tool and the tool is designed; then build the tool the finite element model, modal analysis, obtained the dynamic characteristics, and find out the weak link, put forward the improvement measures and prolong its life. Therefore, the study on dynamic characteristics of shield machine cutter, for the optimization design of domestic tool, has an important significance improve tool life.
Vibration Analysis of Civil Aero-Engine Based on Stochastic Resonance Preprocessing
Authors: Zhang Ying , Liao Heng Yu , Zhao Ge
Published: May 2016

Stochastic resonance (SR) in the bistable system can reduce the noise level, reveal the waveform’s outline prominently, and improve the quality of the system output. Under the support of SR techniques, the extraction accuracy of the civil aero-engine rotor vibration information is lifted, especially when treating the signals contaminated by heavy noise. Results indicate that the SR signal preprocessing method via tuning the relative parameters is effective to reflecting the real vibration of the aero-engine rotor. It can also monitor the short-term failure phenomenon in the sampling data.
Experimental Study on Quadruped Wheel Robot for Wheat Precision Seeding
Authors: Lin Hai Bo , Yi Chui Jie , Liu Zun Min
Published: May 2016

The wheat precision seeding technology provided an advanced agricultural protection for the high yield of wheat. But the lack of an effective agricultural machine made this technology difficult to apply widely. In this paper a quadruped wheel robot to achieve the wheat precision seeding technology was designed. And experimental study was taken under different operating conditions. Because of multiple effort factors, a quadratic orthogonal rotation combination design method was applied in the experiments, and identifying the main factors by analysis. Then the field test was carried out according to the main factors. The experiment results showed that the qualified rates of seeding exceed 93% in different sowing speed. That reached the agronomic requirements of wheat precision seeding.
Crankshaft Mould CNC Machining Based on CAD/CAM Technique
Authors: Guo Ting Ting , Feng Xian Ying , Sun Teng Jiao
Published: May 2016

Taking the CY4105 crankshaft mould as the research target, this paper introduced the CNC machining method based on CAD/CAM technique. At first, structure of the mould was introduced. Then, machining method was introduced, including blank setting method, cutting tool selection, machining method selection and technological parameters setting method. After that, generation method of the mould machining programs was introduced, including tool path and G codes generation. At last, the mould was machined by a vertical machining center, and the results show that the machining accuracy is high.
A Method of Pitch Error Compensation for the Open Numerical Control System
Authors: Ding Yan Yu , Wang Tai Yong , Liu Qing Jian , Dong Jing Chuan , Li Bo , Liu Zhe
Published: May 2016

The traditional fixed pitch error compensation method exists some defects, such as sampling points are not comprehensive and the necessary compensation points are easy to miss. Faced with these problems, this paper presented a new pitch error compensation method based on the open numerical control system. With this method, the traditional measurement points were serried, and more pitch error data were measured. Then calculated the error data with the cubic spline interpolation computation method, and the compensation location and value were obtained according to the accuracy requirement. The pitch error compensation was completed when the data inputted into the open numerical control system with a defined format.
Gantry Robot Dynamic Analysis Based on Lagrange’s Motion Equation
Authors: Mahir A.I.I. , Deng San Peng , Qi Y.M.
Published: May 2016

The dynamic problem is defined as the way the motion of the robot arises due to the torques and forces applied at the joint by the actuators. The motion undergone by robotic mechanical system should be as, a rule, as smooth as possible, abrupt changes in position, velocity, and acceleration should be avoided. Indeed, abrupt motions require unlimited amounts of power to be implemented, which the motors cannot supply because of their physical limitations. In this paper an analytical solution for the dynamics of 3 DOF gantry robot presented to achieve those goals, so our aims is to model the dynamics of gantry Robot for simple pick and place application. Equations of motion are derived using the Lagrange equations of the second order, the dynamical model of robot was developed, and the gantry robot system was modeled in SOLIDWORKS software environment and it was simulated using ADAMS software. The manipulator is composed by four basic modules defined as module X, module Y, module Z and terminal arm, where is connected the end-effector.
Research on a Motion Law Surveying Aparatus of a Cam Follower
Authors: Liu Meng Ying , Sun Jian Jun , Zhao Wei , Zhang Ting Ting , Liu Zhi Wei
Published: May 2016

An apparatus is developed in this paper, which surveys the motion law of the CAM follower. The apparatus is comprised of the frame body, motors, transmission system, execution system, control system and data acquisition system. The displacement curve, speed curve and acceleration curve of CAM are drawn by analyzing the signal from the dial indicators. This apparatus can provide technical data for the mechanical principle course as well as scientific research work.
A Hybrid Machining Database System Using Case-Based Reasoning and Fuzzy Technology
Authors: Sui Xian Feng , Huang Chuan Zhen , Zou Bin , Liu Han Lian , Zhu Hong Tao , Wang Jun
Published: May 2016

In order to fulfil the actual request of machining process to the machining database system, according to the characteristics and requirements of machining process, the fuzzy technology and case-based reasoning method were introduced to the design of machining database system. The reasoning process of case-based reasoning method and three main aspects of the fuzzy model were discussed. The match of cases and fuzzy comprehensive evaluation were introduced. The function of high-speed machining database was analyzed and the structure of the database was described. The users can use the database to acquire the overall solutions about high-speed machining.
Adaptable Material Coding Method for Product Lifecycle Management
Authors: Xiao Xin Hua , Wang Tai Yong , Tian Song Lin
Published: May 2016

Accurate material data shared in product lifecycle is the basis of manufacturing industry informationization. But material coding rule is usually different in enterprises. The code rule definition model based on code segment unit was proposed, and the segment unit was divided into four types as flow, selection, input and conversion according to code generating way. The concept of code segment structure tree was proposed to support the code method’s adaptability. The E-R model of adaptable coding system was described. The integration model of coding system, CAD, CAPP, PDM and ERP was put forward. Based on the model, generating code before design, generating code after design and generating code offline modes were proposed. Taking a specific material code rule in an enterprise as an example, the coding system’s application method was studied. The example shows that the proposed coding method is adaptable and effective.
3D Printing Technology Impact on Development of Industrial Design
Authors: Li Xiao Dong , Zhao Fan
Published: May 2016

Development of 3D printing technology brings revolutionary changes to the future of manufacturing. Based on the development of 3D printing technology and application prospects, this paper analyzes the positive effect of 3D printing technology on industrial design process, industrial design concepts and also some negative issues in the development process, such as intellectual property rights arising. What’s more, it discusses the advent of 3D printing technology which is the catalyst of future industrial design development cycle, the generation of "design of the package" model and the development of industrial design from standardization to individuation.
The Digital Manufacturing Equipment and Development of High Speed and High Precision with Monitoring and Intelligent Maintenance
Authors: Liu Heng Li , Dong Jing Chuan , Wang Tai Yong , Yu Zhi Qiang
Published: May 2016

With the development of science technology in aerospace, automobile and ship, energy and military, the product parts space type face increasingly complex and surface quality requirements more stringent. So there are higher requirements to the digital manufacturing equipment to realize high speed and high precision machining. This paper summary the related research in condition monitoring, remote control, fault diagnosis and intelligent maintenance, and based on the lack of monitoring and diagnosis technology of whole life cycle, unperfected quality control technique, the lower intelligent level in the current equipment, it establish full range monitoring and the whole life cycle of the intelligent maintenance system and present fault diagnosis, control and maintenance solutions for the whole life cycle, and point out the new development direction of the integrated monitoring and intelligent maintenance in CNC equipment.
Study of the Dynamical Model for Manufacturing and Materials Market
Authors: Wang Z.G. , Sun Y.Q. , Zheng Y.
Published: May 2016

Econophysics is a new interdiscipline where physics concept and methods are applied to financial analysis. For example, the application of theoretical physics in the modeling of financial markets has aroused wide concern. In the process of random fluctuation of prices in financial markets, many nonlinear dynamical problems are hidden in set coefficients and assumptions, resulting in the invisibility of market price fluctuations and unavailability of hidden benefits in fluctuations. Based on the analysis of price fluctuation mechanism in financial markets, this paper analyzes the characteristics of price fluctuation, and constructs the dynamical model of price fluctuation by means of physics theory, thereby providing a theoretical reference for the control and prevention of transaction risks.
On the Construction of Visual Image Design System of Machine Tool Products
Authors: Xu J.F. , Gao Z. , Ding Y.H. , Ji X.M.
Published: May 2016

Based on the concept of product image and the relationship between product image and brand image, and through the analysis of the five key elements in the visual image of machine tool products, which are continuously applied to the visual image design process of single products, series products and family products, a visual image design system of machine tool products is consequently constructed in the end, which is of practical significance in enhancing enterprises’ brand image and market competitiveness.
Structural Design and Improvement of Spindle in Five-Axis Wood Engraving Machine
Authors: Zhang Lei , Liu Qing Jian , Wang Tai Yong , Li Hong Bin , Tian Wei
Published: May 2016

In the wood engraving industry, the double swing motor spindle or the double rotation motor spindle is often used as the spindle of five-axis wood engraving machine to achieve three-dimensional sculpture. However, the rough and motor spindle may interfere with each other during machining. Hence, many small regions of rough cannot be machined. To solve this problem, an anthropomorphic double-swing-head mechanism is designed. Instead of motor spindle, the designed mechanism is used as spindle of five-axis wood engraving machine. The level of automation and machining scope of the machine are improved. The workload of subsequent artificial modification is reduced. Then, the machining efficiency and quality of wood products are enhanced, and their production costs are reduced.
Study of Vehicle Jerking Problem during Clutch Engagement Based on Numerical Value Analysis Method
Authors: Cheng Xiang Bin , Zhang Wei Min
Published: May 2016

The impact caused by clutch engagement or disengagement leads to vehicle jerking problem. To solve the jerking vibration, the model of the power train and the process of the clutch engagement is built up, and the numerical relations between jerking vibration and key factors (such as the stiffness of clutch disc, the stiffness and damper of side shaft and flywheel) are established, the validity of the model is verified by comparing simulation results and results of measurement, finally the key factors influencing the vibration amplitude and frequency are identified by vehicle tests.
The Design and Development of a Kind of Antenna Pattern Far-Field Verification Test Stand Based on Level Acquisition
Authors: Liu Xiao Hu , Zhang Zhen
Published: May 2016

The antenna pattern far-field measuring site is important to measure antenna accurately, most of the measuring sites have some problems, which make some deviation comparing simulation results with the standard existence, and will block the design and development of antenna. Therefore, on the basis of the common antenna pattern measurement method, a set of antenna far-field test equipment with level acquisition has been designed, and based on that device some calibration and test methods of antenna pattern suitable for outdoor was proposed. According to this method, it is possible for the same test site to contrast and check the testing data, and the accuracy of the site can be verified and corrected by comparing the measured obtaining within a certain range of the standard level data.
The Influence of Non-Uniform Impeller on the Cross Flow Fan Noise
Authors: Yang Zhi Qiang , Wu C.J.
Published: May 2016

The aerodynamic noise of a cross flow fan with uneven blade spacing in room air-conditioner was simulated by computational aerodynamic acoustics (CAA) method. It is detailed to analyze the vorticity distribution of the flow field and the power spectral density of measured points’ pressure fluctuations, and the results demonstrate the non-uniform impeller used in this paper can significantly improve internal flow characteristics. Thus the broadband noise got reduced.
A FE Modelling Method for the Thermal Characteristics of High-Speed Motorized Spindle
Authors: Wang Jia Rui , Feng Ping Fa , Wu Zhi Jun , Yu Ding Wen , Zhang Jian Fu
Published: May 2016

Finite element simulation is an effective method to study the thermal characteristics of high-speed motorized spindle, how to improve the simulation accuracy has become the key point of this research field. This paper presents a FEA method using ANSYS to precisely predict the thermal characteristics of high-speed spindle. Firstly, the heating and cooling characteristics of high-speed spindle are analyzed, main heating source, convective heat transfer coefficient, and thermal contact resistance are calculated. Secondly, FEA model of the machine center is built, the temperature field and thermal deformation of the spindle system are simulated. Thirdly, an experimental system to test thermal characteristics is designed, simulation results are compared with the experimental results. The result shows that the simulation errors are controlled in a relative low range, the FE modelling method can precisely predict the thermal characteristics of the motorized spindle.
Analyzing Out-of-Plane Vibration of a Rotating Ring with Wave Propagation
Authors: Huang Di Shan , He Hong
Published: May 2016

Wave propagation is introduced to analyze out-of-plane vibration problem of a rotating ring. Harmonic wave solutions are found for the coupled equations of the axial and torsional motion. Wavenumber spectra and phase velocity map are obtained, and the ratio of axial displacement to torsional displacement and the cut-off frequencies are determined. Examples for the free vibration of the uniform rotating thin ring are given to illustrate the validity of the wave propagation. This research will be valuable in the application of a solid cage in high speed roller bearing.
Effects of Wide-Area Operation Environment on the Bogie of High-Speed Train and Solutions
Authors: Wang Peng , Wang Tai Yong , Jing Lu Yang , Liu Zhe
Published: May 2016

High speed railway system in China has developed rapidly in recent years but the operation environment of China has a great deal of differences between Europe and Japan. In the paper, a definition of wide-area operation environment is proposed and its effect on the bogie of high-speed train is analyzed, also some solutions are given.
Experimental Investigation of Dynamics of Assembly with Typical Mechanical Joint
Authors: Liu Xin , Sun Bei Bei , Chen Jian Dong , Xue Fei , Jiao Ren Qiang
Published: May 2016

Mechanical joints have a significant influence on the dynamics of assembled structure due to its discontinuity, uncertainty, frictional contact and micro-slip along the interface. To study the effect of mechanical interface on vibration behavior of industrial product, it is necessary to capture vibration data and investigate modal properties. In order to study effects of typical mechanical joints, double plates coupled with bolted joint are manufactured. Corresponding welded specimen was also manufactured for comparison and reference. Specimens were suspended by two flexible nylon cords for a free–free boundary condition and series of modal tests were carried out. Experimental results reveal that the preload in bolted joint affects the vibration behavior of assembly greatly, and the dynamic stiffness and natural frequency could be enhanced by increasing preload values of specimen. Bolted joints give rise to more frictional damping capacity within lower preload range in this test and welded specimen shows up much higher frequency and similar damping ratio.
Kinetic Properties of Hybrid Vibration Screen with Two-Translation and One-Rotation
Authors: Wang Cheng Jun , Li Long , Meng Xiang Rui , Liu Qiong , Zhang Tian Yu
Published: May 2016

To meet the need of modernized coal dressing, topology theory was used to build a kind of hybrid mechanism 2PRRR-R which can work as a main excitation mechanism of three freedom degree hybrid vibration screen with two-translation and one-rotation. Next, D′Alembert’s principle was introduced to establish a kinetic model of vibration screen frame and surface, and kinematic equations of directions of vibration screen frame and surface was achieved. Then, ADAMS was used to perform kinetic simulation of vibration screen, and kinetic parameters of the hybrid vibration screen was finally tested on multi-dimensional vibration screening test bench. The research shows that kinetic parameters’ numerical simulation of hybrid vibration screen with two-translation and one-rotation basically agrees with spot test value, which verifies the feasibility of the mechanism design, that the screen frame is of two motion freedom, that screen surface is of three motion freedom degree, that the rotation of the screen surface is relatively independent and controllable. The research provides further study of kinetic properties and development of hybrid vibration screen with two-translation and one-rotation with workable reference.
Modeling and Analysis of Single Hydraulic Props in Coal Mines
Authors: He Tao , Yu Cao Feng , Wu Xiao Lei , Deng Hai Shun
Published: May 2016

This research is focused on dynamic performance of water hydraulic single hydraulic prop, the mathematical and AMESim model of single hydraulic prop are established. And the drop hammer is introduced to simulate the impact load of the surrounding rock acting on the prop. The performance parameters of prop retract displacement and cavity pressure are used as the research objects. The working process of single hydraulic prop is reproduced by the simulation. And the influence of safety valve parameters on the support system is analyzed. The results show that: increasing maximal valve core stroke and dead volume or reducing valve damping hole diameter can improve the support performance of the single hydraulic prop. But the influence of equivalent damping has two sides. For support system, decrease damping can improve the support performance, but for the safety valve, reduce the damping make the valve core stability decline. In addition, the pressure overshoot of the optimized system is 18.3%, adjusting time is 0.5s and the retract displacement is 10mm. The dynamic performances meet the technology requirements of the coal mine safety production of China.
Simulation, Experiment and Optimization for Thermal Characteristics of a Machine Tool Spindle System
Authors: Li Dian Xin , Feng Ping Fa , Zhang Jian Fu
Published: May 2016

Taking a vertical machining center as an example, thermal characteristics of the spindle system were researched by finite element simulation and experimental test. Firstly, temperature field and thermal deformation of the spindle system were simulated considering boundary conditions of the finite element model, such as heat sources, convective heat transfer coefficients and thermal contact resistances between joints. Accuracy of the simulation was verified compared with test. The results shows that key areas of temperature rise locate at spindle bearing; thermal deformation of Y and Z directions are large; thermal characteristics of the spindle system has little influence on other parts. Thermal characteristics of the spindle system were optimized by changing structures and sizes of the cooling passage located at the headstock, and effectiveness of the optimization was verified by finite element simulation. The research results provide guidance for thermal characteristic simulation and optimization of a machining center.
Study of High-Pressure Physical Properties of Marine Heavy Oil
Authors: Kang S.Q. , You Y.P. , Feng M.Y.
Published: May 2016

This paper obtains the formula for calculating fuel dynamic viscosity based on the Barus formula and Eying formula from both macroscopic and microscopic perspectives, studies the mathematical model of fuel bulk modulus changing with temperature and pressure based on equation of state for gases and solids, and computes the fitting formula and correlation coefficients of dynamic viscosity and bulk modulus based on IFO 180 test data. The result indicates that the calculation models for fuel dynamic viscosity and bulk modulus are effective.
Hydrothermal Aging Test Study of Double-Glazed Module
Authors: Wei Wei Hua , Zhu Ya Nan , Xue Tong Ming , Xu Jing Wei , Xie Si Yuan , Yuan Cheng Rong , Wang Tong Yue
Published: May 2016

Weathering performance of PV modules is an important indicator of the solar cell module reliability. By conducting hydrothermal aging test for a group of double-glazed modules according to IEC612165 standard (terrestrial solar modules environmental test method) in this paper, the leakage test data and power test data of modules can be drawn after hydrothermal test. Results of the test show that: modules occurs partial delamination after hydrothermal aging test, but did not appear serious appearance defects specified in IEC61215 and power loss is within the allowable range, and all of these have certain value for reference to mass production of modules.
An In Situ Raman Spectroscopy Study of Load Transfer for Carbon Nanotube Film
Authors: Li Qiu , Qiu Wei
Published: May 2016

The load transfer of CNT films under tensile loading at different scales was studied by using in situ Raman spectroscopy. The single-point and plane mapping Raman spectrum data was collected during the film tension to monitor the load transfer process of CNTs and CNT bundle network, respectively. The reason why the CNT film had well strength and ductility and low Young's modulus was revealed.
Cellular Automaton Modeling of Dynamic Recrystallisation Microstructure Evolution for 316LN Stainless Steel
Authors: Ji Hai Peng , Zhang Li Ge , Liu Jing , Wang Tai Yong
Published: May 2016

Based on the theoretical model and physical mechanism of dynamic recrystallization (DRX) in metal materials, the dislocation density change, nucleation and grain growth model during the process of DRX are taken into account. And according to the nucleation driven by dislocation and grain growth kinetic, transformation rules are made. A modeling methodology coupling fundamental metallurgical principles based on amended nucleation rate with the cellular automaton (CA) technique is here derived to simulate the 316LN.The two-dimensional CA model uses quadrilateral element and periodic boundary condition and Von-Neumann neighbor type. The influence of strain, strain rate and deformation temperature on dynamic recrystallization volume fraction and average grain size are analyzed on the basis of established CA model.
Study on the Friction Factor and High-Temperature Friction Resistance of Semi-Metal Frictional Materials
Authors: Wang Yue , Zhou Yuan Kang , Nie Hua Wei
Published: May 2016

The orthogonal experimental study is carried out to study the Incorporation of different proportion of functional components and the effect on tribological performance among semi-metallic friction materials. A test is conducted for each sample on XXD-MSM constant speed tester in accordance with Brake Linings for Automobiles (GB5763-2008). The friction factor and high-temperature abrasion resistance properties are evaluated along with the obtaining of optimal formula, and the mechanism of affecting the tribological properties is analyzed on the worn surfaces by using a scanning electron microscope (SEM). The study results indicate that the high-temperature friction stability could be deeply affected by the adequate content of steel fiber, Kevlar pulp, potassium hexatitanate whisker and cashew nut shell. The mechanism of High-temperature tribological behaviors are the thermal decompositions. The thermal decomposition of organic matter might greatly weakened the bonding effect. The thermal decomposition of tribo-film fall off as lamellar chip under the effect of friction stress. The addition level of nanoparticles is 3%, the sample’s tensile strength, tensile strength, hardness index and noise level are better. If the modified resin is further applied, this formula can be close to the index of excellent Chinese industrial product JF04-20.
Synthesis and Characterization of Graft Copolymers of Acrylic Acid onto Starch
Authors: Zhang Y. , Zhao L. , Ma K. , Mao G.Z.
Published: May 2016

A novel starch-g-poly (acrylic acid) hydrogel was prepared by graft-copolymerization among starch, acrylic acid in aqueous solution with potassium persulfate as an initiator, N, N-methylenebisacrylamide as a crosslinking agent. Characterization of the graft copolymer was carried out by X-ray diffraction, FTIR and SEM analytical methods. Swelling kinetic analysis in distilled water was done to study the swelling behavior of the product. The results show that the product exhibits water absorption of 786g/g in distilled water at ambient temperature. It has been proved that the grafting of acrylic acid onto starch was successful and the aggregation of phase of native starch was changed from semi-crystalline state to amorphous aggregation state due to copolymerization.
The Microstructure Properties of PbO-TiO2-SiO2 System Sealing Solder for Vacuum Glazing
Authors: Shan Xiang , Miao Hong , Zhang Jian Feng , Wang Hong Jun , Sun Juan
Published: May 2016

Microstructure properties of PbO-TiO2-SiO2 system sealing solder for vacuum glazing was studied. Sealing solder was placed on the sealing glass substrate. Samples were obtained by sintering at different temperatures. The microstructure properties and binding properties with soda lime glass substrate at different temperatures was observed and studied. Micro hardness of the sealing solder after sintering were tested. The results show that in the solder sealing temperature, a transition layer was formed gradually between the sealing solder and the glass substrate as the sintering temperature increases. PbO and SiO2are main ingredients of the transition layer. This layer performed tight connection with the glass substrate after it was completely formed. The interface between sealing solder and soda lime glass substrate showed good performance. PbO-TiO2-SiO2-RxOy system is an ideal sealing material for the production of vacuum glazing.
Analytical Prediction of Geometrically Necessary Dislocation Density during Plane Strain Microbending
Authors: Wang Li Jie , Kinsey Brad L. , Parasiz Sunal
Published: May 2016

As components with proportional feature and tooling sizes are miniaturized, strain gradients through the cross-section increase. This causes strain gradient hardening as the density of geometrically necessary dislocations increases. This will lead to higher required forces in the process than expected. In this paper, an analytical model to predict the dislocation density increases, and thus strain gradient hardening, during microbending is presented. These results match previous research in terms of the feature size where modest and significant strain gradient hardening was observed.
Free and Fixed Abrasive Lapping of BK7 Glass
Authors: Li Jun , Tang Y.K. , Zhu Y.W. , Sun Y. L. , Zuo Dun Wen
Published: May 2016

Fixed abrasive technology which has many advantages is one of the future machining directions. Free and fixed abrasive lapping of BK7 glass was investigated and different material removal modes and surface damage categories by lapping were discussed. The results show that material removal rate is larger for free abrasive lapping than that of fixed abrasive lapping with four abrasive sizes and decreases with diamond size decreasing in two lapping processes. Surface quality is better for fixed abrasive lapping than that of free abrasive lapping at the same diamond size and gets better with the decreasing of diamond size. Fixed abrasive lapping can achieve simultaneously high MRR and good surface quality.
High-Strength Steel Hot Forming Mechanics Performance and Characteristic Experimental Study
Authors: Guo You Dan
Published: May 2016

In high-strength steel hot forming, under the heating and quenching interaction, the material is oxidized and de-carbonized in the surface layer, forming a gradual change microstructure composed of ferrite, ferrite and martensite mixture and full martensite layers from surface to interior. The experiment enunciation: Form the table to ferrite, ferrite and martensite hybrid organization, completely martensite gradual change microstructure,and make the strength and rigidity of material one by one in order lower from inside to surface, ductility one by one in order increment in 22MnB5 for hot forming;Changes depends on the hot forming process temperature and the control of reheating furnace gas content protection, when oxygen levels of 5% protective gas, can better prevent oxidation and decarburization;Boron segregation in the grain boundary, solid solution strengthening, is a major cause of strength increase in ;The gradual change microstructure in outer big elongation properties, make the structure of the peak force is relatively flat, to reduce the peak impact force of structure, keep the structure of high energy absorption capacity;With lower temperature, the material yield strength rise rapidly,when the temperature is 650 °C, the yield strength at 950 °C was more than 3 times as much.
Literature Review of Jet Machining
Authors: Geng Xiao , Shi Yan Bin , Lv Yuan Yuan , Dong Shu
Published: May 2016

Jet Machining has significant advantages in processing precision, processing speed, environmental protection, and social benefits, etc. For years, it has been applied in the processing of a variety of materials processing successfully. This paper summarized research achievements on processing characteristics, flow field properties, particle distribution of many kinds of Jets (gas jet, water jet, supercritical carbon dioxide jet ) processing comprehensively and cutting performance for different materials (flexible material, brittle material, super hard materials). It will offer reference for further researching work and design of this novel method. In the meantime it will promote the application of jet processing in industrial production.
Mathematical Modelling the Process of Cup Wheel Precision Grinding of Rotating Concave Paraboloid
Authors: Xia Fu Yi , Xu Li Ming , Hu De Jin
Published: May 2016

A novel principle of cup wheel grinding of rotating concave quadric surface was proposed. The mathematical model of machining process was established to prove the feasibility of precision grinding of rotating concave paraboloid based on the introduced principle. The conditions of non-interference grinding of concave paraboloid were mathematically derived. The processing range and its influence factors were discussed. The trajectory equation of abrasive particle was concluded. Finally, the math expressions of numerical controlled parameters was put forward in the process of grinding of the concave paraboloid.
Design on the Main-Axis in Big Power Inverted Umbrella Aeration Machine Based on Genetic Algorithms
Authors: Li Xiao Ping
Published: May 2016

Genetic Algorithms is a new method, which has good robustness in optimization design for complex system. In this paper, we make the mathematical model of optimization design for the main-axis in big power inverted umbrella aeration machine by studying Genetic Algorithms. Using coding method, we complete the optimization design of the main-axis in big power inverted umbrella aeration machine.