Key Engineering Materials Vol. 572

Abstract: Guide rails which take place in structure of elevator, are the important elements for safety of elevator systems. They have attached together end to end with the fishplates and bolts, and are anchored to wall with brackets. Connections between guide rails and brackets are provided by clips. To ensure the safe operation of elevators, the guide rails, fishplates, brackets, bolts, clips have enough strength against to loads and forces which affect these elements. In this study, shear tests are performed to examine mechanical properties of bolts and clips which are used guide rail anchor element. The results which are gained from stress calculations and experiments are compared and interpreted.

Abstract: The structure design of the underwater diamond wire saw test bench system was conducted for the research of the diamond wire saw cutting mechanism. Through the kinematic analysis of the test-bed parallel lever mechanism, parallel loading mechanism equation was derived, which provided a basis for the cutting force distribution of the loading bow.Software ANSYS was used for the modal analysis of the test bench mechanism. As the theoretical analysis and calculation result showed, the test bench design in this paper realizedthe validation of the diamond abrasive cutting principle, which can serve as guidance for theprocessing and manufacturing of the test bench.

Abstract: Based on the bi-directional evolutionary structural optimization (BESO), the method of determining the adhesion position of the damping material is proposed in this paper, which is applicable to the vibration damping of ship plate. In this method, the needed amount of damping material is taken as the constraint condition, and the maximization of one natural vibration frequency of the structure is taken as the target function. A thin plate structure with both ends constraints has been taken as an example to get the best topology structure of its adhesion damper by taking the BESO method. The result of optimization shows that it still meets the damping requirements when the needed amount of damping material decreases by about 50% of the original amount. The reasonable result demonstrates the effectiveness and engineering value of the method.

Abstract: An analytical method is derived for the free in-plane vibration analysis of annular plates with general boundary conditions. Under this framework, all the classical homogeneous boundary conditions can be treated as the special cases when the stiffness for each restraining springs is equal to either zero or infinity. The improved Fourier series solutions for the in-plane vibrations are obtained by employing the Rayleigh-Ritz method. A numerical example is presented to demonstrate the accuracy and reliability of the current method.

Abstract: Considering the ship's limited space, high speed and miniaturization have been design directions in marine turbo generator set. The shared foundation with steel plate welding is designed to support the marine turbo generator set. Stiffness and dynamic characteristic of the shared foundation will directly affect the stable operation of the turbo generator set. The paper established the dynamics analysis model for the shared frame of marine turbo generator set according to the 'Lumped Mass Method'. Taking account of the frequency-domain analysis operability, the operational modal analysis and dynamical response on foundation were carried out by Virtual Lab. Based on these results; the intensity and location of exciting force were ascertained. And then, we designed the shared foundation vibration isolation system, and analyzed the characteristics of the vibration isolation mounting. The result shows that the vibration isolation system can minimize output force transmissibility and reduce the effect of the marine turbo generator set vibration.

Abstract: Underwater vehicle has abroad applications in submarine rescue and deep-ocean workstation and so on. Moreover, mating device strength and skirt mouth pressurize is important condition for working safe. In order to realize reliable mating, endure force analyzing on steady mating to platform was put up and load to finite element model. The computing result of finite element model and experimental value is accordant. The research and experiment on pressurize methods was finished, the result show that O-type pressurize and lip-type pressurize has ensured pressurize reliability. This paper can provide reference for analogy structure Strength and pressurize reliability.

Abstract: The materials and surface treatment of warship cabin walls affect not only the safety but also the habitability. The performances of the specific fire retardant are investigated according to the requirements of Chinese Standard GB8624. The experiment is conducted in Cone Calorimeter. The results show that it is a noninflammable material, which has an excellent flame retardant effect arriving at B1 level of the standard. It provide a diverse selection of cabin materials.

Abstract: One of the most widespread procedures used for building a shrink fit consists in a thermal process in which the hub is heated and lately cooled while the shaft is placed at the assembly final position, so the joint is radialy set. In this paper the contact pressure in a shrink fit is analyzed by means of the numerical simulations using FEA method. We compare the results with those obtained by the alternative building fit process, i.e., the axial press insertion, and, with the ones given by the pressure cylinders theory. Relevant information revealed from numerical simulations, as the stress and strain state after the assembly process, could be useful in the design of shrink fitted joints improving their performance during their life in service.

Abstract: Quantitative determination of stress concentrations factors (SCF) in interference fits joints is highly relevant since they are not given by the theory of pressure cylinders commonly used for designing them. We study the capability of using a full chamfered hub as a geometrical design for reducing SCF. Stresses distributions and stresses concentrations factors are analyzed as a function of parameters that define the hub geometry with the aim of optimizing the design of proposed modified hubs. To achieve this goal, diverse numerical simulations by means of the finite element method (FEM) were carried out in order to quantitatively estimate the stress state existing at hub-shaft interface.

Abstract: Dual-frequency capacitively coupled plasma (DF-CCP) etcher has become the mainstream in dielectric etcher. By building a 2D axisymmetric model of 300mm DF-CCP etcher in CFD-ACE+ software, plasma simulation experiments are carried out by orthogonal design. Then a process model based on simulation results is proposed to analysis influence of key process parameters including high frequency voltage, low frequency voltage, and chamber pressure and center/edge flow ratio on chamber plasma characteristics. Finally, to get high plasma uniformity and plasma density, process optimizations are carried out.