Advanced Materials Research Vols. 503-504

Abstract: It is of great significance for the design of ejection mechanism and the control system of automatic ejection machine that the initial ejection force of injection mould can be calculated. According to the production status of basin type insulator epoxy injection mould, the influencing factors on the ejection force were analyzed. The calculating formulae of initial ejection force for cavity with different structures were derived and verified using methods of mechanics analysis, arithmetic average and the thoughts of molding mechanical performance submits Hook’s law. The verification result shows that the initial ejection force can be better estimated and used as a reference to design.

Abstract: The dispensing manipulator is one of the focus-researching projects at present,according to 5-DOF dispensing robot,firstly we completed designing the structure diagram of manipulator,and then used the mathematica calculation to finish the forward solution of kinematics about 5-DOF dispensing maniputor,which is derived the overall transformation matrix of the maniputor.finally we verified the correctness of the overall transformation matrix through the actual example.It is proved that the method have provided a reference for the kinematics equations of general maniputor.

Abstract: Based on Integral Stochastic Finite Element Method (ISFEM), the structural reliability of solid propellant grain was analyzed. Viscoelastic finite element method was determined and ISFEM is utilized to improve calculation efficiency. The thermally accelerated aging experiments at 40°C，50°C，60°C and 70°C were carried out, and the mechanical property parameters were investigated. Considering the randomness of Poisson’s ratio and relaxation modulus, structural reliability and its variation tendency solid rocket motor grain under the ignition pressurization case were investigated in combination with failure criterion. The results show that the reliability of SRM grain descends not evidence before twelve years, but quickly descends after 12 years.

Abstract: Comparative finite element method (FEM) analyses of resistant spot welding (RSW) and laser beam welding (LBW) on stainless steel railway vehicles to assembly the framework and the side wall penal were conducted. The stress and strain of RSW joint and LBW lap joint were calculated under the same loading conditions by FEM simulation, respectively. The analyses revealed that not only the stress concentration occurred but also the maximum stress existed in the RSW joint compared with LBW lap joint under the same load. In contrast, LBW technique had more advantages than that of RSW technique in joining the car body framework and side wall penal of railway vehicles in the respects such as smaller deformation, better air tightness, and better appearance of car body and higher efficiency of processing.

Abstract: High-power LED street-lighting with advantages including long lifespan, great luminescent efficiency, lower power consumption and superior environmental performance has received more and more attention. However, the lifespan of corresponding LED drivers fails to match with that of LEDs. The main reason is that in tight and confined spaces, high heat flux cannot be emitted to surroundings, which lead to the increased temperature of electric devices in LED driver. In this paper, high conductive micro heat pipes (MHPs) are applied in the cooling system. Firstly, the Icepak thermal simulation software is applied in analog contours of temperature of interior driver. Then experiments are carried out to measure the temperature of electric devices of LED driver. The results indicate that internal temperature of LED driver is decreased by 5°C when MHP is applied, compared with the original thermal design. The capacitor and MOSFET which are sensitive to heat and easy to damage run under optimized temperature.

Abstract: Pump efficiency as an important parameter in the modern production of oil field. How to get the actual pump efficiency accurately and quickly is very important. In order to obtain accurate pump efficiency, the ground dynamometer card of the oil well is taken as the research object. According to find the traveling valve factual open and close position, we can get the actual efficient stroke and the load change of sucker rod. Then pump efficiency is computed using the actual efficient stroke and the load change of sucker rod.

Abstract: Vibration isolator with displacement restrictor is used to best control vibration and shock simultaneously. This can’t be realized without a proper mechanics model. The drop weight test on the polyurethane isolator with displacement restrictor was discussed. The generalized mechanics model of vibration isolator based on the MAXWELL element and gap element was established, which can help the shock characteristics analysis and parameter optimization of the isolator.

Abstract: According to the characteristics of functional fibers and the performance requirements of underwear product, we selected chitin ,cotton and wool fiber as raw material, and developed two different structural underwear fabrics, Based on the experimental test, the wearability hydroscopicity, vapor permeability and anti-bacterial property were analysed and studied. The results showed that the designed fabrics have excellent hydroscopicity, vapor permeability and anti-bacterial function. as well as excellent wearability. Therefore, the underwears made of these fabrics willl not only be comfortable to wear , but also have excellent health care function. Therefore, they are ideal fabrics for making high–quality underwears

Abstract: At present, main AC power systems of advanced fighters all apply digital controllers with microprocessors. The signal input and output circuits are vulnerable to the effects of electromagnetic interference, which may cause air-power-off fault. The paper analyzes the electromagnetic environment on the aircraft, discusses the airborne electromagnetic compatibility by comparing domestic and international contents and limitations of the electromagnetic standard. Furthermore, it proposes measures to resolve the electromagnetic compatibility

Abstract: The change law of basic paste material performance in the pipeline must be studied to verify long distance transportation in coal mine after the ratio of paste material is completed. This paper introduced simulation system which was developed by us and the pipeline transportation experiment was done. The change law of paste material parameters was studied including collapsed slump, segregation degree and density with pipeline experiment. And the contents of this paper could provide theoretical guidance for field paste filling.