Advanced Materials Research Vols. 479-481

Abstract: A new method is presented in the paper. The fatigue life reliability of submarine cone-cylinder shell is investigated, based on the combination between the methods of conventional Monte Carlo and classical probabilistic fracture mechanics. Firstly, Monte Carlo method is employed to obtain the reliability of given initial fatigue life. Secondly, the two induced factors M1 and M2 in the paper are estimated according to the initial fatigue life and the reliability. Thirdly, based on the two factors, the other fatigue life reliability is obtained by using classical probabilistic fracture mechanics method. Finally, numerical cases show that the proposed method is more efficient without accuracy loss for fatigue life reliability compared with Monte Carlo method. This method can also be applied to predict the fatigue life reliability of analogue structures.

Abstract: Problems of vibration fatigue exist in the field of aeronautics and astronautics widespread, which endangered the safety and reliability for structures of aircraft. Vibration-exciter-based fatigue testing system was designed and a method for fatigue testing of the resonating structure was proposed. In test, natural frequency of the test pieces was tracked by the exciting frequency. Experiments are carried out for the typical components with different working condition. One is with given strain, and another is with given force. Results indicate that impacts of the strain amplitude, the damping, the natural frequency and the boundary conditions on vibration fatigue life are obviously.

Abstract: MATLAB is a visualization of facing the scientific computing outstanding scientific and technological application software, it can make the abstract of pure theoretical study way evolved into the theory and application in the closely combining way, It takes the scientific computing, the visualization and programming focus on a convenient use environment, more easy to grasp. This paper mainly introduces the design of the user interface by using MATLAB. User use the interface, inputting system open-loop transfer function simply, namely can easily finish system analysis and series compensation. not only can avoid trival manual calculation and difficult manual drawing, improve the design accuracy, but also greatly shortened the design time. There has practical application value.

Abstract: Based on the wind load calculation model increases Suspended Platform vibration characteristics of wind vibration coefficient, and gets Suspended Platform natural vibration period and inherent frequency by ANSYS finite element modal analysis, then determines the wind vibration coefficient, calculates the wind load of Suspended Platform in working state and non-working state. Aiming at three different conditions, analyzes the platform structure in the wind load the stress intensity and deformation. Through analysis to finds the most dangerous positions of Suspended Platform in three different conditions, provides effective references for the L Type Suspended Platform in wind-resistant design and optimization design.

Abstract: There are abundant coal bed methane resources in China, and recovery technology is considered a very important part in the development of coal bed methane. At present, coal bed methane production areas are still adopting the tubing liner pump, but because of the special working environment, in the pumping process, the fine breeze (sand) and other solid particles entering into the pump barrel is likely to cause the pump stuck, pipe string buried by sand and other issues. In view of the above problems, based on the ordinary tubing liner pump, through the increase of the anti-litter bypass style traveling valve housing and fixed valve housing, outside liner jacket, sand reservoir and liquid in tee joint measures we developed a new type of CBM special anti-clogging drainage pump and adopted finite element analysis software ANSYS to complete key parts of strength calculation. The use of this pump will effectively reduces the blocking of fine coal particles (sand) and other solid particles, decreases the pump's checking operation and workload of sand bailing, consequently improves efficiency, reduces overall operating costs.

Abstract: The limit internal pressures of the nozzle-cylinder intersection with different dimension are calculated by nonliner FEM and are used to determine stresses of this structure in elastic analysis.The elastic nominal stresses linearized by stress-along-a-line method are classified at the danger location and the limits of kinds of nominal stress intensities are taken as the stress assess criteria of the nozzle-cylinder intersection. The results show that, in the range of parameters for calculation, the primary local membrane stress intensity SII is less than or equal to 2.0 times design stress intensity Sm,and the primary membrane plus primary bening stress intensity is not more than 2.1 times Sm.

Abstract: Dropout may be happen to round thread connection by main reasons of design and process of product, material’s property, make-up torque or make-up position, field operation problems etc.. Casing’s property has get a high improvement with the development over the past decade in China. But the number of connection dropout accident didn’t declined obviously. These lead to great economy loss and safety hazard had taken place. Research on a round thread connection pullout case was carried out combining relative theorys with tests. Macroscopic analysis and dimension measurement and material’s physical and chemical properties were checked for casings and couplings. Thread inspection and full-scale tests were done for casing simples that are same lot with dropout. Comprehensive analysis was carried out on these results. The results showed that dropout failure was ascribe to two main causes. One is make-up location cann’t reach standard location at field end, and the other is incorrect holding position on coupling in the course of making up.

Abstract: Inner support design criteria is put forward and systematic cornering theory model is established. Displacement differential equation is deduced, and then the radial stress and hoop stress expressions of inner support under the condition of high speed are proposed on the basis of assumption of axisymmetric problem, which makes sure that the inner support is safe under normal pressure and high speed condition. Research results are helpful for inner support structure design of run-flat tire system.

Abstract: The iron ladle is a kind of large metallurgy equipments and used for collecting and carrying iron water. According to the factual demand of produce, some corporation wanted to enlarge the capacity of the idle from 65t to 75t only by increasing the height of ladle. This paper is aimed at the changing idle which the capacity is 75t and built up its 3D numerical model. According to the constant of the iron water capacity, it used the method of modeling to find the angle of the ladle taphole and made sure the ladle couldn't overturn automatically by studying the process of overturning. Then this paper worked out the overturning moment so that it could provide mechanics data for the analysis of the finite element and the reformation of the corporation.

Abstract: Based on experimental research on plain concrete columns with high strength concrete core, the formula to predict the bearing capacity of concrete columns with high strength concrete core under axial compression loading was brought forward in previous paper, in order to verify the formula whether right, axial compression test including 3 concrete columns with high strength concrete core and 1 ordinary reinforced concrete column were completed, and the failure characteristic was analyzed additionally. According to experimental results, it can be shown that the failure modes of concrete columns with high strength concrete core are similar to that of ordinary reinforced concrete columns, however, the bearing capacity of concrete columns with high strength concrete core is significant higher compared with that of ordinary reinforced concrete column; the results of the bearing capacity obtained by the formula (2) was in good agreement with the experimental results.