Advanced Materials Research Vols. 655-657

Abstract: With the development of digital design and processing and the explosive growth of the demand for two-dimensional CAD engineering graphics, more attention has been paid on the security and the copyright issues of engineering graphics. In this paper, an improved reversible watermarking algorithm in wavelet domain for two-dimensional CAD engineering graphics is proposed. Firstly, the watermark information is preprocessed by compound chaos sequence. And then, block the graphic and extract all vertexes in each blocks of the 2D CAD engineering graphics, Log-polar Mapping (LPM) and wavelet transform are done to them respectively to achieve the invariance of affine transform. Finally, the encrypted watermark is embedded into detailed coefficients by using improved quantization index modulation (IQIM) scheme. Compared with the original previous algorithm, theoretical analysis and experimental results show that the proposed algorithm has not only good visibility and good reversibility, but also stronger robust against the attacks such as transformation, rotation, equal scaling and entity deleting, tampering or adding etc.

Abstract: The optimal saving energy permanent magnet lifting chuck has been designed. Working principle of this technology is introduced. Magnetic circuit design is carried out by finite element method (FEM). At the same time, a perfect self-acting driving system has been invented for picking and releasing loads fast and conveniently without using any electricity at all. Industry prototype was manufactured, and it verified that the proposed lifting permanent magnetic chuck was feasible.

Abstract: For the low pumping demand of daily production per well of low permeability oilfield, a diameter of 25mm soft sealing small diameter piston-type subsurface pump is designed, and an external traveling valve to ensure that the valve still application of standard parts is adopted, while reducing the pump barrel diameter. In order to solve the problems of pump leakage increasing with wear, automatically compensate for soft seal ring is adopted in piston design. The liquid pressure of the pump barrel is changed in the pump working process, so that the sealing ring is deformed outwardly. When the pump reaches the upper stroke, the gap between the pump barrel and the piston reduced, and further improve the sealing effect. The innovation of structure and the selection of new materials can reduce the difficulty of pump processing, as well as can extend the maintenance cycle. This paper introduces the overall structure and sealing characteristics of soft sealing small diameter piston-type subsurface pump. If the soft sealing small diameter piston-type subsurface pump and real-time variable frequence control technique of pumping unit combined, a more reasonable machine rod pump combination can be provided to achieve ultra-low permeability oilfield stripped well efficiently pumping.

Abstract: The impeller is the core component of ventilator, and its operation safety has a crucial influence on the unit reliability. To improve the safety of the impeller, 3D solid modeling of the impeller is made with Solid Works software and the static and dynamic strength characteristics of it is calculated with ANSYS software in the paper. The results show that the contact edge round between the blade and the wheel cover can effectively relief the stress concentration and reduce the maximum stress of the impeller.

Abstract: The motion law of single metal progressive cavity pump was studied through motion simulation. Then, the finite element analysis software ANSYS was used to analyze the distribution characteristics and the influencing factors of the contact pressure. It was pointed out that the single metal progressive cavity pump has the ability to withstand high temperature and the differential pressure mainly influences the wear. At last the reasonable range of the clearance was given.

Abstract: Based on 3D solid modeling and assembling, the motion simulation of the whole hydraulic support is performed with Pro/E software and the accuracy and reasonableness of their actions and designs are tested. According to the static and dynamic analysis of hydraulic support with Pro/E software, the structure of hydraulic support is optimized.

Abstract: Automotive transmission shaft is the main component of vehicle power; it directly affects the force conditions and the life of the stability of auto transmission. Therefore, mechanical analysis and optimum design of car's drive shaft is very important. Finite element analysis and reliability design of auto transmission are performed by Pro/MECHANICA software in the paper and the intermediate shaft on the vehicle drive shaft is analyzed and optimized.

Abstract: Through combining with VC++ and APDL language of ANSYS, the finite element optimization design for lower beam of the YJ32 hydraulic press was completed used complex method. The global optimum solution was obtained in the case of meeting the casting process requirement. The casting process requirement is that the thickness of a casting is almost the same and the inner wall thickness should be a little smaller than the outside wall thickness. The optimal result reduces the structure weight and the cost of the lower beam. Meanwhile, this provides a new method for the finite element optimization design about castings.

Abstract: On the base of explaining Multi-Objective Optimization Problems (MOOP) and Collaborative Optimization Techniques (COT), this paper puts forward an original and efficient approach—Collaborative Optimization Technique for Multi-Objective Optimization Problems (COTMOOP)—which combines Collaborative Optimization (CO) techniques and Evolutionary Algorithms (EAs). It has been developed so as to facilitate the organizations and increase the performances of complex coupling systems design and optimization. The newly method has been succeeded in applying to the design and optimization of excavator boom mechanism that is a complex coupling system. The optimal solutions can prove that the approach is efficient and practical.

Abstract: According to the basic principle of the shearer’s travelling mechanism to build the virtual prototype based on UG and ADAMS, and then carry out kinematics simulation of this virtual prototype .The error of angular velocity of every level transmission between virtual prototype and theoretic values . The results can be taken as the guideline for future structural design and dynamic simulation analysis.