Advances in Mechanical Engineering

文章题目 页数

作者: Tao Chang
摘要: PLA fiber is a green eco-fiber of excellent properties and sustainable development, with adequate sources of raw materials, low energy consumption, good biodegradability, and excellent physical and mechanical properties, thus the development of this product not only has considerable economic benefits, and also has excellent social benefits. In this paper, through comprehensively testing the properties of PLA fiber, it carries out the systematical analysis and research on the Tests of PLA fiber length, fineness, over length, double length, and defects, combustion property, heat resistance, and hydrolysis property, etc. several aspects.
作者: Yuan Li Yang
摘要: By analysis on the realization for RFID (Radio Frequency Identification) technology, TC35i module of CTI (Computer Telecommunication Integration) technology, this article provided a solution and technology realization method for Logistic Information Perception Interactive System. The Logistic Information Perception Interactive System is a combinational application of Internet Of Things (IOT)) RFID, CTI and internet technology, the system consists of three levels system structure of perception level, network level and interaction level, which is supported by RFID reader, RFID logistic tag, TC35i module and other software and hardware as well as interface technologies, integrates and build logistic business flow and information perception interactive section link for supply chain, forms interactive system of RFID logistic, TC35i equipments, user mobile communication, internet communication and other sections. In the Logistic Information Perception Interactive System, it uses AT signal, API (Application Programming Interface) interface program to design short message logistic business interactive program based on TC35i and RFID, realizes isomerism application of communication, technology in terms of logistic information application means, realizes the ubiquitous links and distribution management of perception logistic.
作者: Yi Bo Li, Dao Hui Wu, Ming Hui Huang, Xin Jiang Lu
摘要: 800MN forging press uses plate laminated parallel structure as the main bearing mode, where the force transfer and the stiffness match play key roles in achieving satisfactory performance of the equipment. Although the traditional design methods can obtain desirable stiffness or strength for bearing structure, they less consider the effect of manufacturing errors on the system performance and thus are ineffective. This is because manufacturing errors can cause local structure variation and heavy stress concentration, which may do great harms to the working performance of the equipment. In this paper, a new design approach is proposed to consider the effect of manufacturing errors to the system performance. First, a three-dimension finite element model of the 800MN forging press is built using Marc, upon which stress distributions and concentrations under different combination modes of manufacturing errors are studied. Then, combination law of manufacturing errors is established and validation is carried out through physic test.
作者: Qiu Xia Hu, Dong Jian He, Jie Tian, Peng Cheng Zheng
摘要: Identification of poisonous plants especially outdoor diet was practical for tourism in exciting outdoor travel. A new method called Poisonous Plants Retrieval System Based On the Mobile Device was proposed in this paper. The used mobile devices in this system were based on J2ME and the selected development platform was Eclipse. Firstly poisonous plants were classified into four main categories according to the subject categories of plants. Next, each of four main categories was classified into four sub-classes by analyzing the toxic parts or similar positions of plants. Then, to store the characteristics information of the subjects and poisonous position of plants, a symmetric two-dimensional array matrix form was developed. Finally the cell phone software retrieved known poisonous plant to help people make outdoor diet safe with high convenience.
作者: B. Li, J. Yu, Suo Qing Yu, A.B. Wang, Y.H. Jiang, Y.H. Zhang
摘要: The forging method with horizontal V-shaped anvils (HVA) is effective in the control of inner stress states, metal tissue, etc. FEM numerical simulation is conducted for the HVA forging method, under various processing parameters. The results show that during HVA forging, the transversal and axial stress states in the middle part of forgings are influenced by not only the ratio of the anvil width to billet height (anvil-width ratio )but also the ratio of the blank width to billet height (blank-width ratio) and the reduction ratio, while the end parts are influenced little. Among those processing parameters, the reduction ratio plays an important role. When the reduction ratio is 5% or 10%, it is possible to obtain axial and transversal tensile stress. When the reduction ratio is larger than 15%, it is easy to obtain two-way compressive stress. Therefore, in order to control the two-way tensile stress, big reduction ratio should be adopted. Small blank-width ratios result in the forgings cracks because of transversal tensile stress in common flat-anvil stretching method. On the contrary, even if the blank-width ratio is small, transversal compressive stress can be generated in forgings for the HVA forging method, only if the matching of the anvil-width ratio and the reduction ratio is suitable. The feature of the HVA forging method benefits the preventing forgings from inner cracks. The results provide the theoretical foundation for the application of the HVA forging method.
作者: Prachya Peasura
摘要: This research was to effect of electrode force on the tensile shear and nugget size of the resistance spot welding. The specimen was austenitic stainless steel 304 grade sheet metal 1.2 mm thickness. The electrode force are 1, 1.5, 2.0, 2.5, and 3.0 kN apply to the specimen. The replications in each treatment are 20 follow JIS Z 3136:1999 and JIS Z 3139:1978. Factor control, welding current 7 kA., time current flow 7 cycle and electrode tip diameter 6 mm. The welded specimens were tested by tensile shear testing according to JIS Z 3136: 1999, macro structure testing according to JIS Z 3139: 1978 and analysis results by using One-way ANOVA .The result showed that electrode force had affected on tensile shear and nugget size at 95% confidential (P value > 0.05). The low force induced the gab between specimen increasing then the current flow difficult to pass and both of gab between specimen and nugget seize had increase (Q=I2Rt). When the resistance increased so that fusion zone will have a high heating. It had affected to nugget size, heat affected zone and mechanical properties decreasing. The electrode forces are complete 2.5 kN. tensile shear 9.21 kN and nugget size 5.82 mm. The data can be applied to be used as process monitoring of resistance spot weld quality
作者: Guang Zhu Zhou, Xu Wei, Chen Yu
摘要: This paper is mainly to study earth pressure on Gcrw used as a new kind of supporting structures in the excavation of deep foundation pits in soft soil region. On the basis of the simulation of step by step excavation by using big finite element software Abaqus/CAE and considering three-dimension elastoplastic stress state, the characteristics of different earth pressure are systematically discussed upon practical engineering. By comparing simulation results with calculated results based on calculation formula of Rankine Theory, it can be seen that the earth pressure in active zone is different from theoretic active earth pressure and earth pressure at rest while walls and soil in the gridding are regarded as a whole, which is greater than the former and somewhere similar to the latter, the earth pressure in passive zone is bigger than theoretic value of passive earth pressure, it is the tensive force from partition wall that prevent the front wall from overturning. These conclusions will be helpful for design and construction of new retaining wall.
作者: Li Jie Feng, Jin Feng Wang, Zhao Hui Li, Hua Ke Zhong
摘要: The paper describes a type of serial running mode that boost pump provides water floating and the main submersible pump runs in a no-diving mode. The practice show that this mode can effectively solve the drainage problem at the inclined shaft under the condition of large water inflow and no track, and overcome the drainage problem under the coal slime silting condition. This mode also expands the application of high-power submersible pump theoretically.
作者: Yu Qing Liu, Yan Xiang Wu, Hai Bo Huo
摘要: In this paper, we established a bridge three-dimensional finite element model for the structural dynamic analysis according to the geometry and material properties of a bridge Li Gong Yi Qiao at Wuhan University of Technology. On the other hand, we tested the dynamic characteristics of the bridge under environmental excitation by means of bridge sensors arranged at different points. The modal parameters of the bridge were identified through fitting the admittance circle. The comparison between the measured results and the theoretical studies has shown that the low-order vibration frequency and mode obtained from finite element analysis generally consistent with those from test. The finite element model provides a scientific basis for condition monitoring of the bridge in actual operations.
作者: Darwin Sebayang, Deni S. Khaerudini, Hendi Saryanto, M.A. Othman, Mat Husin Saleh, D. Fredrick, Pudji Untoro
摘要: This paper investigates the efficiency of two consolidation processing techniques prepared by spark plasma sintering (SPS) and hot pressing (HP) which allow obtaining fully dense nanostructured materials. FeCr powders were sintered by using spark plasma sintering (SPS) and hot pressing (HP) sintering techniques over sintering temperature up to 1000oC. The microstructures of the sintered end-products were characterized by Scanning Electron Microscopy (SEM). X-rays diffraction line profile analysis was adopted to analyze the crystallite size of starting and sintered FeCr using Williamson–Hall method. The density of the sintered specimens was measured by using the Archimedes method. The result indicated that the dense specimen with relative similar density and approaching the equilibrium state obtained in shorter time and lower sintering temperature by spark plasma sintering compared to conventional hot pressing. The FeCr specimen prepared by SPS showed more effective to retain nanocrystalline and better mechanical properties than those prepared by HP. The diffraction investigation revealed that the grain growth was not significant in SPS process compared to HP, which would enhance the mechanical properties of the SPS sintered FeCr.