Applied Mechanics and Materials Vols. 511-512

Abstract: Wear is one of the main failure modes of gears in the meshing performance, and contact pressure is the key factor to determine the wear of gears. The main purpose of this paper is to investigate the contact pressure distribution and evolution laws in straight bevel gear meshing. Based on a 3D FE model of the specific loaded assembling straight bevel gear pair, the influence of friction coefficient f, torque T and elastic modulus E on the contact pressure of straight bevel gear in a meshing circle is studied. The results show that the contact area and contact pressure increase dramatically with the increase of the torque. The contact area decreases and the contact pressure increases with the increase of elastic modulus. Friction coefficient almost has no effect on the contact area and contact pressure. This research has great theoretical significance to reveal the wear mechanism and improve the meshing performance of straight bevel gears.

Abstract: Electrostatic chuck (ESC) is one of the key components in IC manufacturing process, which applies the principle of electrostatic adsorption to clamp the wafer on its surface. In such a system, electrostatic force is considered as one of the most important indicators. The method of modeling and simulation of electrostatic force by COMSOL software is proposed, and the accurateness is validated by comparing the results with those from reference. Then, the simulation of ESC in real manufacturing process is finished using the above method, which focuses on the effects of dielectric materials and voltage on electrostatic force. The research can offer references for the design of ESC, and it has significance to reduce experimental cost and improve the reliability of the equipment.

Abstract: The flame arrester sheet of explosion-proof valve with flame arrester was optimized to enhance its capability to reduce pressure and extinguish flame. Firstly, it introduced the principle of operation of explosion-proof valve with flame arrester. Secondly, the optimization object and variable were determined. Software FLUENT was adopted combining with homogeneous design method to carry out the numerical calculation. Then, regression analysis method was used to analyze the results and got the regression model of optimization objective. The results had shown that the regression model had its significance. Lastly, based on regression model of optimization objective, the solution of multi-objectives optimization was obtained applying linear weighting method. It is of importance to guide flame arrester structural design of explosion-proof valve.

Abstract: In order to improve working frequency band and damping effect of a dynamic vibration absorber, a new kind of dynamic vibration absorber is presented. Its resonant frequency could be real-time adjusted by adapting the stiffness of the spring. The vibration attenuation characteristics are analyzed theoretically and numerically. According to simulation analysis, effects of geometrical parameters are researched and optimum geometric parameters are determined. The damping effect was simulated in a flat structure, the results show that the working frequency band and damping effect of the DVA are both remarkable.

Abstract: Finite element static analysis is a method for optimizing the design. It results from the combination of mathematical optimization method and modern computer technology. It enables a certain design to get better parameters under a variety of restrictions, thus making an optimal value of design index. In the traditional design process, Based on the initial design, the designers, with their own experience or accumulated experience by others and expertise, could ultimately get a more satisfactory one through repeated experiments, comparison and improvement. Experiencing long design cycle and consuming many human and financial resources, this approach may have found a better solution, but it is generally not able to find the optimal design. Fortunately, the finite element static analysis method provides the approach to an efficiently optimal design.

Abstract: Vault installation is one of the important parts of the LNG storage tank construction. Due to the large size, installation of high accuracy and the influence affected by complex factors such as wind load in hoisting process, the installation procedure is always controlled by artificial way which is low efficiency and a big risk. In this paper installation process is optimized. According to the structural characteristics of vault plate, this paper proposes a new kind of installation guide equipment and analyses the process of guiding, which can help vault plate realizing itself position. The equipment can greatly improve the installation accuracy and working efficiency, and also can reduce the risk of installation. The technology of vault plate installation of LNG storage tank has important practical value and significance.

Abstract: Dome gas lift is the technical difficulties of a large LNG (liquefied natural gas) tanks in the process of construction. The sealing structure is one of the core link in the process of the gas lift. In this paper, the seal structure of large LNG storage tank dome gas lift is studied. A new kind of sealing structure is designed by using gap seal. This paper has carried on the simulation analysis with ANSYS software to verify the feasibility of new type sealing structure. This kind of sealing structure can reduce the friction in the process of gas lift. It also can use the smaller contact area to achieve good sealing effect. The method has important practical value in enhancing the security of gas lift of LNG storage tank dome.

Abstract: Rail transport conveyer is special transportation equipment that is widely used in the field of metallurgical industry. It is the key to ensure equipment operation efficiency on a production site. But the low lift system efficiency and poor reliability are difficult technical problems in the enterprise. In this case, rail transport conveyer uses the worm gear and screw nut lifting mechanism. The project carries on rail vehicle lifting system modeling and dynamic simulation study through Solid Edge ST5 and ADAMS, combined with simulation technology, virtual prototype design. Research purpose is in order to match the coefficient of friction between the screw and screw nut better, and to match different speed ratio for the drive gear pair and the lifting mechanism being in empty back to travel and work schedule. Another aim is to match the speed of the lifting speed and walking speed, and to reduce the error probability. Results show that the motor can get better speed matching relation with lifting mechanism through research, further optimizing the structure of lifting system parameters. Through the analysis and structure optimization, we can improve the reliability of rail transport vehicle lift system, and implement efficient fast for copper anode lifting and positioning precision. The ultimate goal is to achieve vertical hanging in electrolytic cell anode plate, and to make electrolytic operation to achieve the best state.

Abstract: This paper introduces working principle of screw oscillating hydraulic cylinder. Structure parameters and process parameters influence on mechanical efficiency is analyzed, simultaneously, structure parameters and process parameters influence on volumetric efficiency is also analyzed. the maximum mechanical efficiency and optimal spiral angle are acquired. Total transmission efficiency model is established. Transmission efficiency experimental test is carried out, experiment test efficiency is basically in accordance with calculated efficiency.

Abstract: Based on case-based reasoning in the intelligent design of complex mechanical products described hierarchical classification and coding, combined with matrix description will be giv en the attributes of the instance method, each layer instance description of the property and to establish a link between an instance, child inherits the parent's characteristics discussed on the basis of the CNC lathe Knowledge Base rule base and instance library