Advanced Materials Research Vols. 1033-1034

Abstract: The principle of high pressure water jet technology and its unique characteristics and advantages were introduced in this paper, specific applications of the high pressure water jet technology in coal mine production and security aspects were analyzed. It was widely used in coal mine tunneling, preventing and controlling ground pressure and gas outburst, the application of the dedusting fan, cutting the coal mine machine and cleaning and descaling downhole equipment. Finally, the feasibility and safety of the high pressure water jet technology in coal mine was summarized, and the article made prospect for its future application.

Abstract: The article is to study the development of computer-aided design of X-ray microtomography - the device for investigating the structure and construction three-dimensional images of organic and inorganic objects on the basis of shadow projections. This article provides basic information regarding CAD of X-ray microtomography and a scheme consisting of three levels. The article also shows basic relations of X-ray computed tomography, the generalized scheme of a X-ray microtomographic scanner. The methods of X-ray imaging of the spatial microstructure and morphometry of materials are described. The main characteristics of an X-ray microtomographic scanner, the X-ray source, X-ray optical elements and mechanical components of the positioning system are shown. The block scheme and software functional scheme for intelligent neural network system of analysis of the internal microstructure of objects are presented. The method of choice of design parameters of CAD of X-ray microtomography is aimed at improving the quality of design and reduce of costs of it. It is supposed to reduce the design time and eliminate the growing number of engineers involved in development and construction of X-ray microtomographic scanners.

Abstract: The input shaft of coal pulverize reducer happened fracture after 3 months in operation. The metallographic examination, composition of chemical elements, mechanical properties, macroscopic examination and SEM of the fractured shaft were investigated. The result showed the metallographic and composition of chemical elements of input shaft complied with relative technique requirements. The fracture was typical brittle fracture; the fracture mode was low cycle fatigue brittle fracture. As the input shaft of surface was not required for carburization, the surface hardness was low; extension strength and yield strength were below the requests of product quality certificate, the crack source generated in the stressed side of keyway. The position design of keyway was not suitable which accelerated the fracture.

Abstract: Solving forward displacement is the difficulty of the 6-SPS parallel kinematics calculations, to make sure solving forward displacement easily, in this paper, added a initial multi-DOF drive to the 6-SPS parallel mechanism's moving platform in the ADAMS environment to make kinematical simulation, to get simulation of inverse kinematics solution and strike a theoretical inverse kinematics solution in the MATLAB environment, and prove the correctness of simulation of inverse solution. The inverse simulation position be used as input parameters to drive this parallel mechanism, by the solving forward displacement, results showed that the forward displacement is consist with the initial-DOF-driven values, indicating it is correct. It proves the use of these methods can be simply and easily calculate the required 6-SPS parallel mechanism positive solution, which can provide the reference of such institutions' solving forward position and control.

Abstract: In recent years, new energy supply (energy self-sufficiency) technology which can replace the traditional battery supply has become a hot topic in global research field of microelectronic devices. A new low-frequency trapezoidal bow-shaped piezoelectric energy harvester (TBPEH) was proposed. The geometric model and finite element model (FEM) were built. The static analysis, modal analysis and harmonic response analysis of the TBPEH were discussed by using the Finite Element Analysis(FEA). Then traditional rectangular bow-shaped piezoelectric energy harvester(RBPEH) was compared with the new TBPEH. Simulation showed that the TBPEH could harvest energy more effectively than the RBPEH. The output voltage was increased by 135% with little change in resonant frequency, and indicator of the inhibition of side peak (SPI) which represented the capability of broad-band energy harvesting rose 11.2%. The TBPEH resonance frequency is 34.1Hz, which can be applied to the low frequency environment.

Abstract: Hydro-generator unit is the most important energy conversion device in the hydropower, which is directly related to the safety and reliability and stable operation of the hydroelectric power plant. When the turbine generator rotor winding inter-turn short circuit occurs, the proposed method using load curve electromagnetic characteristics analysis, the use of before and after the failure to find the relative change in the excitation current failure rate as the identification method, the criterion may reflect the severity of the failure, perform theoretical calculations, and thus the inter-turbine generator rotor windings short circuit simulation, consistent with the conclusions of the theoretical analysis.

Abstract: Production section testing technique is an important kit technique of horizontal well development. And traction robot technology is the core technology. Downhole driving unit is a very important part of traction robot, it can be used to implement a variety of sports instruction of control system, so that the traction robot can walk in the pipeline, to sent the test equipment to the destination, and the crawling round can be recovered automatically when the system is powered down. This paper give out the overall design of downhole driving unit, and then the traction regulating mechanism has been optimized: first, created a mechanical model of traction control mechanism, and then optimize the important structure parameters of the adjustment mechanism.

Abstract: In order to resolve the problems that many units are intersect and mutual restraint in the safety evaluation of emulsion explosive continuous manufacturing, the safety evaluation model based on uncertainty measurement theory was built, then this model was used to evaluate the safety of emulsion explosive continuous manufacturing in one explosive industry. The evaluation results show that: the information entropy and confidence identifying criterion were respectively used to ascertain the evaluation index weight and identifying criterion, by these ways, the evaluation results of this model are more objective; and the evaluation units can be selected flexibly according to actual situation, the calculation of evaluation model is simple, so the evaluation results can offer decision basis for explosive industry to make good management.

Abstract: Microwave regeneration research has been conducted for the modified activated carbon (MAC) which has adsorbed 2,4,6-TCP. The effects of microwave power, microwave irradiation time and MAC loading amount for regeneration are studied.The results show that, at the beginning, the adsorption volume increases with the increase of the microwave power. However, when the power is over 450w, the adsorption volume begins to fall. The adsorption volume increases with the irradiation time,rises to its peak when irradiated for 6 minutes.The adsorption volume increases with the loading amount and rises to its peak when the amount is 5g.

Abstract: For the low temperature waste heat recovery problem, waste heat recycling system was designed based on the heat pipe heat transfer technology of hydrogen in industry. The system is mainly in the process of hydrogen production by methanol steam reforming, using heat pipe excellent thermal conductivity, isothermal and thermal response characteristics, it will be in the low temperature waste heat of flue gas as heat source, in the heat pipe under the action of high efficiency heat transfer, through technology improvement, structure optimization design, achieved high efficiency, energy saved heat transfer to the methanol in the reaction system of hydrogen production, achieved the goal of remaining heat to be recycled.