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我国目前可以用来铸造铜质螺旋桨的材料,除规范规定的Cu1(1级锰青铜)、Cu2(2级镍锰青铜)、Cu3(3级镍铝青铜)、Cu4(4级锰铝青铜)四种类型的铜合金外,还有GB1176《铸造铜合金技术条件》中的ZCuZn40Mn3Fe1(40-3-1锰黄铜)、ZCuZn35Al2Mn2Fe1(35-2-2-1铝黄铜)、ZCuAl9Fe4Ni4Mn2(9-4-4-2铝 相似文献
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我国目前可以用来铸造铜质螺旋桨的材料,除规范规定的Cu1(1级锰青铜)、Cu2(2级镍锰青铜)、Cu3(3级镍铝青铜)、Cu4(4级锰铝青铜)四种类型的铜合金外,还有GB1176《铸造铜合金技术条件》中的ZCuZn40Mn3Fe1(40-3-1锰黄铜)、ZCuZn35Al2Mn2Fe1(35-2-2-1铝黄铜)、ZCuAl9Fe4Ni4Mn2(9-4- 相似文献
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为了提高轴类零件的使用年限,增加其耐磨性和耐腐蚀性,可用铝青铜在轴的表面进行堆焊。文章介绍了如何选择合适的焊接工艺、焊接方法以及借助合理的焊接辅助工装,使得轴类零件表面堆焊铝青铜的质量更加可靠,满足使用要求。 相似文献
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瑞典《J.W.Berg AB》公司生产的变距桨侧推装置,可由桥楼遥控,主要用于拖船、拖网渔船、挖泥船、电缆敷设船以及其它类型的船舶上.3或4叶片的D型螺旋桨,功率为220~417 kW,特别适用于小型船舶.叶片用铝青铜制成,桨毂用锰铜制成.3或4叶片的H型螺旋桨,功率为735~29400kW,其叶片和毂均用镍青铜或不锈钢制成.《J.W.Berg AB》公司生产的变距桨、其特点为: 相似文献
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铝膏铜铸件在熔炼过程中不仅易产生氧化铝夹杂和氢,且氢被铜液吸收后形成气孔。因此,在熔炼铝膏铜时要进行精炼处理,以除渣去气。 1.生产情况 (1)熔炼过程 我厂生产的系列泵用喷嘴材质为铝青铜ZCuAl9Mn2,熔炼时先 相似文献
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TIG堆焊铝青铜接头组织分析 总被引:2,自引:0,他引:2
采用TIG焊在低碳钢和不锈钢表面进行QA19-4铝青铜合金堆焊,对堆焊接头利用扫描电子显微镜进行组织分析,并探讨了铜钢异种金属焊接接头溶合区的形成及区域划分。 相似文献
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价值观是指人们对价值的性质标准、构成和评价的基本看法和态度,是指导人的行为的一系列基本准则和信条。构建海事核心价值观是时代发展的要求,更是海事自身发展的需要。 相似文献
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This chapter presents a summary of the findings of the workshop on ‘Analytical and Institutional Methods and Frameworks’. The paper discusses the nature of the analytical methods used in the papers presented and the purposes for which they were employed, which were generally to either assist in the planning and operation of public transport or to monitor the efficiency and effectiveness of transport services. Subsequent sections examine issues related to data collection and management, and the more general issue of institutional arrangements. Policy and research agendas needed to support further consideration of the subject are then identified. 相似文献
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介绍青藏高原多年冻土的冻融特性,并结合我局在青藏铁路十二标段的具体施工,分析了冻土的冻融特性及具体防止措施. 相似文献
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Geoffrey Wood 《Maritime Policy and Management》2004,31(2):157-171
This paper explores the current state of coastal and inland shipping in Tanzania. It provides an overview of the state of ports and shipping in Tanzania, and the reasons underlying the present crisis of competitiveness in terms of both global pressures and national and regional dynamics. Problems of competitiveness are at least partially due to under-investment, management failures, skills shortfalls and difficulties in interfacing with the railway network. Less easy to resolve structural problems include the great imbalance between imports and exports, heightened regional competition and ongoing political instability in the Great Lakes region. 相似文献
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风量与风压的简易测量及应用 总被引:2,自引:0,他引:2
锅炉正常燃烧必须有充足的风量,当锅炉鼓风或引风不足将导致锅炉效果恶化,锅炉出力、热效应率明显下降。结合工程实例,介绍结托管简揭测试鼓、引风系统各部分风压、风量,帮助判断分析工程实际问题的简便方法。 相似文献
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Elizabeth A. Wilman 《Coastal management》2013,41(3):211-230
As the controversy over Outer Continental Shelf (OCS) oil and gas leasing continues, with environmentalists and fishermen seeking to block or delay leasing decisions that they think will adversely affect their interests, the need for better estimates of the environmental costs associated with OCS development becomes increasingly apparent. Although high degrees of precision in such estimates may never be economic, let alone feasible, better knowledge would reduce the uncertainty surrounding the magnitude of such costs, and would make it easier to come to grips with the problem and reduce, if not resolve, the controversy. 相似文献