Applied Mechanics and Materials Vols. 494-495

Abstract: Metal cone of the screw rotor and stator rubber bushings are the two main components of the opposed biconinal cone screw hydraulic pump for the seawater. The stator rubber bushing is not only a damageable element, but also the key component deciding the service life and efficiency of the pump. Up to date, none effective method has been found for testing the deformation and enforced state of the stators rubber under the real working condition. For the general conventional screw stator with uniform internal pressure at both ends of the stator bushing enforced and deformed almost the same, as to other case when the cone screw pump stator has rubbers with different cross-sectional size and thickness at its different end, the enforcing and deforming state at different end varies differently. The stator of the opposed biconinal cone screw hydraulic pump is studied in this paper for the case when the stator is uniformly enforced, using finite element analyzing software ANSYS-Workbench , this study concluded the stress, the strain and inner-figure deformation of the screw hydraulic pump stator, the stator rubber and the stator steel thimble. Besides, the characteristics and rules of opposed biconinal cone screw hydraulic pump deformation are summarized as well.

Abstract: Since the element action (e-action) is the smallest motion unit in realizing systems function, its reliability plays an important role in system operating ability. In this paper, a new method of CNC machines reliability analysis based on e-action is proposed. Firstly, the definition of e-action reliability is studied and the mathematical model is built. Then the methodology of FMECA based on e-action is introduced. Finally the grinding carriage feed movement is taken as an example to illustrate the methodology.

Abstract: Industrial design is an emerging edge science, which intersperses throughout the development, production and sales of product. From market research to data reduction and then to the final market launch, every segment permeates computer aided design, which will develop towards to digitization, networked, virtualization, intelligent inevitably.

Abstract: Heavy duty machine tool has some special points, such as large size, complex structure, long cycle at Installation and commissioning, high requirements assembly processes and so on. Therefore, this paper established a mathematical model to transform the origin parts of the gantry machining center into assembly special form and creates a software as a plug-in for Solidworks based on it, proposes an easy but very practical assembly method based on Multi-body system under virtual environment. This method can calculate assembly deviation caused by manufacturing tolerance very quickly, and bring the sensitivity information clearly. Assembly deviation sensitivity and assembly method proposed in this paper can provide a way for the virtual assembly of heavy-duty CNC machine tools, Thus provide an important theoretical basis to improve the performance of the machine

Abstract: This study investigated the wind turbine blade root bolt static strength using the full scale static test, selected the root bolts of 1/4 bridge strain gauge using the finite element analysis method and the dynamic and static strain instrument. The data of the stress loading combined tension and bending bolt were obtained.

Abstract: Aim at solving the problem of ribbing defect is found on cold rolling strips which is caused by bad hot strip shape, analyze the reason from the hot rolling process, and study out that there are some reasons such as uneven wear of rolls can lead to ribbing defect. Roll contour, roll shifting model, rolling plan were optimized and got a geart effect: the hot strip shape being better, the production being more stable, the ratio of ribbing defect decreasing obviously (from 2.2% to 0.3%). The quality of their product has been improved a lot.

Abstract: Ultrasonic elliptical vibration turning (UEVT) is an advanced machining technique for difficult-to-cut materials, in which with frequency in excess of 20 KHz is superimposed on the cutting tools movement. In order to analyze the effect of vibration frequency on cutting forces and cutting temperature, finite element models of ultrasonic elliptical vibration turning were developed. The cutting forces and the distribution of the temperature on workpiece and cutting tool were predicted. It is observed that the cutting forces and cutting temperature decrease with the increase of the vibration frequency.

Abstract: The main purpose of this work was to develop a mathematical model and computer programs for design analysis in composite core-pulling mechanism. The injection mould with slanted guide pillar for two-step core-pulling from the side of the product effects significantly the quality and efficiency of plastic part. The study is a one-dimensional analysis of secondaryejector mechanism, based on a forward marching technique of solution for the simple structure and high safety and reliability. Using the simulation analysis of mechanical system based on Pro/E, the mechanism can solve the problem that plastic parts are difficult to side core pulling in different directions by the use of bevel pillar.

Abstract: A low dimensional precision is one of drawback for the GMAW-based rapid forming technique, which is related to pressure and heat flux on molten pool. To study pressure and heat flux on molten pool, the effect of droplet impinging process must been considered. A three-dimensional numerical model was built to analysis pressure and heat flux distribution on molten pool. Solving the model, it was found that pressure on the cathode by the arc decreases dramatically when the droplet is coming. As to heat flux, the appearance of droplet cuts down it within about 1.5 mm away from arc axial. Out of 1.5 mm away from arc axial, droplets effect on heat flux is not obvious.

Abstract: To improve the damage ability of the hollow-charge warhead, and the utilization of the dynamite, added the prefabricated fragments at the circumferential of the shaped warhead, used the finite element software to calculate the influence of different prefabricated fragments, different shell structure on warhead's EFP and fragments performance, and also the penetration capability of them. The results show that: the performance of the damage elements formed by this anti-armor composite warhead are very well, it can damage the armored vehicles, ships and other targets, the sphere fragment can penetrate 12mm thick armor steel in 60m, and damage personnel in the 240m, EFP can penetrate the armor steel more than 0.5 times of the charge's diameter, this research can provide reference for the further research on multi-using warhead.