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51.
Bomsster is a key load-bearing part of railway lorry bogie.Because of its inherent defects casting-steel bomsster could not meet the demands of the heavy load,acceleration and security for lorry.So forging process is proposed to form it.The forming performance of forging-steel bomsster is analyzed.A forging technology is presented which realizes two forging-steel bomsster parts formed in one die.With the plastic forming simulation software DEFORM-3D,the simulation and optimization of the forming process of forging bomsster has been taken based on 3D rigid visco-plastic FEM theory.Optimized scheme has been used to direct the pilot product.The results of product's testing and application suggest that the new forging technology is feasible and the performance of the product is credibility and stabilization.The factory has realized large scale production of a series of forging-steel bomsster.Remarkable benefits of both economy and society have been achieved. 相似文献
52.
Zheng Xiaoqing 《保鲜与加工》1995,(4):9-17
In view of the complication of compreliensive evaluation to development projectplanning alternatives,an AHP model for comprehensive evaluation to the alternatives is advanced,the way of determinating the weight of each index affecting the aIternatives' quality is expounded,and the general methods of evaluating the alternatives with the indexes are given. 相似文献
53.
Based on the analysis of the status of building construction in China, the development of Assembled Structure System (ASS) can solve not only the problems in construction, but also is the key for realization of building industrialization. On the basis of technique innovations, a study on the structural performance, construction method and precast production of ASS should be carried out to inherit the old one and overcome its demerits. The process reengineering should be done in the construction enterprise to promote the development of building industrialization. 相似文献
54.
Condition assessment on power transformer is an important approach to improve reliability of transformer and provide proper decision-making for condition-based maintenance. For long, static assessment method used in the past has already not adapted to the development of modem electricity transmission and distribution technology. So based on the deficiency of fuzzy synthetic assessment method, matter-element synthetic assessment method is introduced. The method can evaluate transformer condition not only in quality but also in quantity. Because each index weight can be given fairly and fast through improved analytic hierarchy process, which need not carry on consistency chec accuracy of assessment can be improved. Examples analysis has proved that assessment method of power transformer condition based on matter-element theory is rational and effective. 相似文献
55.
This paper takes "how to estimate the complex security of Large Convention and Exhibition Centre effectively" as the research goal.Based on analyzing the difficulties,target system,technical constitution,probing into the architecture,safety science,and using for reference the mathematics,operational research,statistics and modern system theory and method,trying to explore establishing an evaluation methodological system,which is provided with integrated characters on subject.Based on these ways,it exerts "quality to quantity" fuzzy analytical hierarchy process(FAHP) and aims at discussing the safety grade assessment of the Chongqing International Conference Exhibition Center focusing on designing theories.The aim is to enhance the integration of design practice and safe consciousness,strengthen the building safety management,and perfect city public security system.In practice,it is also an efficient tool for favoring values of architectural environmental safety. 相似文献
56.
Wang Xiaoru Mi Linshu 《保鲜与加工》1989,(1):26-35
This paper applies the Gear-4 algorithm to constitute the companion models lor the circuit elements and electromagnetic relays commonly used in relay protective devices. The interface computation, which describes the node equation of companion model and differential equation of mechanical moving part for the electromagnetic Jelay, is also presented. For the reason mentioned above, it makes possible* to solve more accurately the transient process of relay protective devices including electromagnetic relay using the companion model method. The simplicity and effectiveness of interface computation have been proved by the example calcultaion. 相似文献
57.
58.
Wan Ling Li He Xu Jiang Yin Guangzhi 《保鲜与加工》1989,(1):79-85
In this paper the fracture process of specimen,with single crack, double cracks and triple cracks is observed and analysed. The experimental results show that the fracture process of specimen is different because of the differention of the number, the distance and the type of array of cracks. And the fracture propagation of specimen with triple cracks and double cracks is foundmentally the same. 相似文献
59.
60.
180°对称分布的双蜗壳结构在大型离心泵中应用广泛,但目前对双蜗壳内部流动规律的数值研究还相对较少。为了探究双蜗壳流道内部流动规律,利用CFD软件,基于雷诺时均N-S方程和k-ε紊流模型,通过SIMPLE算法进行压力速度耦合,对双吸式HD型石油化工流程泵蜗壳流道内部流场进行了数值模拟,得到了蜗壳内的速度场以及压力场的分布规律,并重点分析了隔舌和扩散段内的流动。数值结果表明,蜗壳内的速度场以及压力场分布相对比较均匀,在隔舌和扩散段内存在一定的回流和涡流,但并不影响泵的良好性能和高效率。 相似文献