Advanced Materials Research Vols. 299-300

Abstract: 35 tons hydraulic overturning machine is the operating equipment that is mainly to make steel coil turn 90 ° and keep steel coil change from vertical position to level position or on the reverse. Because the dead weight value of overturning machine is extreme and the coil's weight which needs to turn is very heavy, the strength of equipment that is a very important design parameter plays a decisive role in the device security. By using the finite element analysis function of COSMOS Works to analyze the strength of overturning machine, which simplifies the design process, improves the design reliability and has value for the design of steel coil overturning machine.

Abstract: Biomass forming technology is an effective way of using biomass energy. Based on the relative technology information from the home and abroad, the “cluster straw” as a new type of fuel briquetting machine has been proposed. According to many kinds of test data forming straw fuel briquetting machine, the force and power parameters were determined. By using the three-dimensional design method, the virtual design molding of cluster straw fuel machine is built. The strength analysis has been done on finger wheel by the finite element method, which came to valuable design data to referring to; wheel-shaped structure was modified to improve the strength.

Abstract: As regards the solution of ensemble elastic stability of assemble and lattice boom with complicated boundary conditions are rarely discussed, it is always plaguing designers. In this article, through analyzing the characteristics of vice-boom and vice-boom strut bar be caused complex deformation under load, based on the deformation relationship among vice-boom, vice-boom strut bar and main-boom ends, establishing elastic stability theory mathematical-mechanical model, using the theory of calculating the Euler critical force, proposed the method and numerical value to determine length conversion factor of assemble boom. This article has an inaugural significance of theory.

Abstract: The multi-facet drill shows good performance during materials are difficultly machined. However, for a new type of the drilling point, the grinding has been the main problem that restricts its application. To properly grinding the drill point confirms the design parameters, the relationship between design parameters and grinding parameters must be resolved. The mathematical model is the key to solve this problem. In this paper, according to the design of the high manganese steel drilling tool, a mathematical model has been established by the plane grinding method to solve grinding parameters, and to achieve improved mechanical grinding of drill point.

Abstract: Aimed at three-translational parallel mechanism, the velocity Jacobian matrix is formulated on the basis of analytical method, so the velocity and acceleration of the moving platform is calculated. Then the velocity and acceleration formulas of all components’ centroids are deduced based on the vector method. The above formulas are very simple and easy to solve. Kinematic simulation is carried out by ADAMS virtual prototyping software. The operating data is obtained, it verifies the correctness of the theoretical calculation.

Abstract: The grind test is detected curve of the grinding surface roughness of cylindrical in use of three-dimensional contour in this paper, major influence factor in the accuracy of surface roughness is proposed in the analysis based on the chatter.

Abstract: Based on the nominal stress method for fatigue life prediction, the model for predicting the fatigue life of mechanical structures under random cyclic load is developed in this paper. The uncertainty of the cyclic loads applied on the mechanical structures is analyzed. With the number of load application as the life index, the fatigue life prediction models of mechanical structures under random cyclic load are developed with the probability weighted method and the Miner linear cumulated damage rule, when the relationships between fatigue life and stress can be expressed as the exponential function and the power function, respectively. Finally, the models proposed are used to predict the fatigue life of train axis.

Abstract: The simulation of squeeze casting process of a magnesium alloy wheel was practice. Using professional casting software, the temperature field during filling and solidification process, and then the potential defects were forecasted and previewed. It was found that there would be shrinkage defects at the center and the junctions between the rim and the spokes of the wheel. It is better to choose a mould temperature for a better cast property at meet of full-filling. Number of programs are analyzed and compared through orthogonal experiment. And the best parameter team is educed through analysis. It is confirmed that the potential micro-shrinkage is reduced by simulated again using the best parameter team. And the cast property is enhanced.

Abstract: Method of vacuum rolling-bonding can be used to produce ultra-thick steel plate over 100mm with continuous casting slab. In this paper, four groups steel plates have been rolled with 10%, 30%, 50% and 70% total reduction ratio respectively. The microstructure of the interface has been analyzed by optical and scanning electron microscopy (SEM). The reaction products formed at the interface have been identified by EDAX. It has been observed that the size and the amount of the reaction products decreased with the increase of the total reduction ratio. The tensile property of the thickness direction has been tested by the universal testing machine. The results indicated that, with the increase of the total reduction ratio, the strength had been increasing from 532MPa to 564MPa, and the plate plasticity became well.

Abstract: In this paper, a butt-welded plate with cracks of different sizes and locations was used to analyze the crack propagation in the residual stress field. A two-dimensional finite element model was established to study the distributions of stress intensity factor along crack front in the residual stress field. Several cases with different crack lengths and angles were investigated. It was found that the distributions of stress intensity factor along crack front were very sensitive to residual stress. The methods and results presented in this paper are capable of providing a reference for the efficient assessment of the effect of residual stress field on the crack propagation behavior. It also implies that proper welding procedures are required for acceptable residual stress distributions to ensure prolonged service life of weldments.