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文中对万家寨引黄工程北干线1号隧洞Ⅳ标使用的155—274型TBM主轴承总成各部件组装过程及其相应的技术要求进行了概要的描述,目的是进一步熟悉155—274型TBM主轴承总成的各个部件并加深对主轴承工作原理的理解。 相似文献
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Finite element analysis of the hip implant is conducted in this paper for representative femoral cross-section geometries and development of stress in the presence of bone cement is elucidated. Differences in cement stresses generated by varying implant cross-sections were compared with conventional features derived from representative implants. The analysis was performed under idealized implant assemblies by constraining the implant movement in the assembly. The cross-sections and implant geometries used are generic and intended to be representative of available geometries. This paper is a part of student research projects, prepared from a series of activities in biomedical implant research currently underway at Ohio Northern and Arkansas Tech Universities. 相似文献
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孙维銮 《自动化与仪器仪表》1994,(3):31-34,38
从理论上和实践上对武钢1700、鞍钢1700改造前后、本钢1700改造前后和攀钢1450精轧机组的电动压下机构在带钢压下时的动特性进行计算和探讨,得出有说服力的结论。主题词: 相似文献
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台北101层国际金融中心之结构施工技术与其设计考量概述 总被引:1,自引:0,他引:1
本文旨在简要说明目前正在施工中之超高层大楼—台北国际金融中心之结构系统、钢结构工程、钢筋混凝土工程基础与深开挖工程等特殊施工技术,并佐以相关之设计考量与施工规划概要,以供工程界做参考。 相似文献
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Steel box sections are usually fabricated from flat plates which are welded at the corners. The welding process can introduce residual stresses and geometric imperfections into the sections which can influence their strength. For some thin-walled sections, large periodic geometric imperfections have been observed in manufactured sections. Subsequent investigations have indicated that the imperfections are in fact buckling deformations i.e. the box section has buckled due to welding residual stresses prior to any application of external load. The welding procedure and the behaviour of the box sections under load has been modelled using a finite element analysis that accounts for both geometric and material non-linearities. Tests have been carried out on box sections with a range of width to thickness ratios for the plate elements. Modelling has been shown to give good correlation with the test results. The conditions for buckling to take place as a result of the welding process have been established. A design method has been proposed. 相似文献
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Woo Gon Kim Sung Ho Kim Woo Seog Ryu 《Journal of Mechanical Science and Technology》2002,16(11):1420-1427
The Monkman-Grant (M-G) and its modified parameters were evaluated for type 316LN and modified 9Cr-Mo stainless steels prepared
with minor element variations. Several sets of creep data for the two alloy systems were obtained by constant-load creep tests
in 550-650°C temperature range. The M-G parameters,m, m’,C, andC’ were proposed and discussed for the two alloy systems. Them value of the M-G relation was 0.90 in type 316LN steel and 0.84 in modified 9Cr-Mo steel. Them’, value of the modified relation was 0.94 in type 316LN steel and 0.89 in 9Cr-Mo steel. Although creep fracture modes and
creep properties between type 316LN and modified 9Cr-Mo steels showed a basic difference, the M-G and its modified relations
demonstrated linearity quite well. Them’ of modified relation almost overlapped regardless of the creep testing conditions and chemical variations in the two alloy
systems, and the parameterm’ was closer to unity than that of the M-G relation. 相似文献
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