Advanced Materials Research Vols. 834-836

Abstract: For the existing squeezing machine of metal shell,in a lot of squeezing experiments, we can discover that the depth of clasp mark of different metal shell are diverse in the same experiment, adjust the stress point distribution of cylinder in the squeezing positioning plate and squeezing mobile plate, obtain the experimental data and analyze it, analyze the effect of multi-point force distribution on the clasp mark of the metal shell.

Abstract: The perforation impact dynamic loads can destroy or disable the tubing strings. The perforated completion process was simplified to explosion of ordinary explosive charge in perforation liquid. The dimensionless expression of perforation impact dynamic loads was derived based on main influence factors and then its engineering calculation formula was set up. A well perforation operation in western Sichuan as an example, the oil tubing strings security was analyzed by the perforation impact dynamic loads from the engineering computation formula. The results show that the tubing strings only occur elastic spiral bucking and do not occur plastic deformation which are in line with perforation operation results on site.

Abstract: The internal flow fields of liquids in space between casing and rotating disk have been obtained by using CFD.The curves of shear stress on the disk and static pressure on casing wall against radius are also gained in various viscosity and different leakage conditions.The results indicate that the shear stress is influenced significantly by the leakage in the space.The shear stress on the disk decreases with the increase of leakage,especially in small radius.However, the reduction rate of stress gets smaller with the increasing of liquid viscosity.The greater the viscosity is, the higher the shear stress is.The growth of shear stress along the direction of radius is greater than in small viscosity.

Abstract: Hydraulic motor is an important hydraulic component in hydraulic control system, so the analysis of its performance is very important. The piston couple is one of the most important frictional pairs in axial piston motor, this paper studies the forces on the piston couple of swash-plate axial piston motor. It deduces the mathematical model of forces analysis in arbitrary phase of the cylinder, and the forces of a type of axial piston motor are analyzed. And it gives suggestions for structure optimal design of piston couple.

Abstract: In order to optimize the dimension of a manipulator, the optimization requirements are analyzed. Then the mathematical model and optimization objectives are established. Next, the lengths of the manipulator are optimized by Matlab genetic algorithm optimization toolbox. The structural strength and bearing installation space are considered at the same time. The trajectory and transmission angle are compared. Finally, the lengths which meet the use requirements are obtained. This optimization method provides a reference for similar mechanism.

Abstract: Planar multi-bar mechanisms are widely used in the machinery industry. In this article, the hybrid mechanical press, a typical planar seven-bar mechanism is investigated. The dynamics mathematical model is established based on the simultaneous constraint method. On the basis of it, a relevant simulation is carried out by virtue of MATLAB. Thus, the dynamic response law and stress state for the key part (ram) of the mechanism are yielded. The simulation results show that this method is much more effective and efficient and provides a theoretical foundation and a better analytical approach of simulation for design and analysis of complex hybrid-driven mechanical equipment in the future.

Abstract: In this paper, use double Laplace transform, in the image space deep beam deflection and corner of analytic is obtained,Then use the numerical inversion of Laplace transform ,time domain dynamic response curve is calculated. Also apply to the combined effects of sandwich beam bending and torsion beam dynamic response calculation.

Abstract: Took two layers of single span lateral sway semi-rigid connecting steel frame to bear vertical load function as the research object, adopting finite element method for solving the bucking load of the whole losing the stability of the semi-rigid connecting steel frame. Using based on the energy method and the three parabolic interpolation deflection curve function to obtain the relationship between the both element ends of internal force and displacement and introducing semi-rigid beam element stiffness matrix and geometric stiffness matrix of element integrate the global stiffness matrix which contains the flexibility of the connections and the component geometry nonlinear, thus deducing the stability characteristic equation of semi-rigid steel frame. And the MATLAB language composition program is applied to calculate the buckling load of overall losing stability of the semi-rigid steel frame, thus obtaining the buckling load of semi-rigid steel frame. The method is a very effective numerical calculating method which can solve the stability problems of relatively complicated stress conditions or relatively complicated structure composition conditions and it can also satisfy the requirement of higher calculation accuracy, easy for programming and calculation and of great practicability.

Abstract: A linear temporal value of the displacement and stress on the boundary over a time interval is adopted, and the boundary integral equation calculating dynamic SIF (Stress intensity factor) in time domain is set up by the travelling characters of elastic wave and the dynamic extention of Betti’s reciprocal theorem. The dynamic SIF of the cracked finite plate is calculated. The comparison shows that the computational results agree favourably with other published results .

Abstract: When vehicle driving on turning, its easy to rollover because of high speed and large steering angle. Aim at Sports Utility Vehicle, a rollover dynamic model of three degree of freedom is established and used to simulation test of typical cornering. The relation of steering wheel, steering wheel rotation speed and suspension stiffness to vehicle rollover characteristics was analyzed by Fishhook simulation test. Then, the sensitivity analysis was carried out to confirm the biggest factor influencde vehicle rollover.