共查询到20条相似文献,搜索用时 125 毫秒
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介绍了一种微型电机轴的绿色加工方法,它突破了微型电机轴传统的加工方法,改车削两端半球面为冷镦,变外圆磨削为冷拉.由于是无切屑加工,节省了材料;由于取消了热处理,节省了能源;由于省去了磨削工序,节约了成本,减轻了对环境的污染,因而实现了微型电机轴的绿色加工. 相似文献
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介绍了采用装置自产瓦斯为介质的芳烃抽提破真空工艺,节约了氮气消耗,降低了生产成本,保护了溶剂,提高了装置综合经济效益。 相似文献
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阐述了国内外汽车制造企业售后服务信息化发展现状,分析了汽车售后服务业务流程,研究了ASP模式的协同应用平台,并根据汽车售后服务的业务特点构建了基于协同应用平台的售后服务系统体系结构。最后,设计了系统的模块,描述了其基本功能,并对系统进行了开发。 相似文献
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王振道 《机械工人(热加工)》2008,(18):80-81
阐述了液压油箱的结构和制造工艺。通过改进结构,方便了焊接操作;通过细化工艺,确定了焊接规范,从而控制了飞溅,减少了油箱内的清理量,提高了清洁度。 相似文献
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研制了一种新型直线超声电机,首先对其驱动机理进行了探讨,对定子表面质点椭圆运动的形成进行了分析,结合电机输入电压信号的时序阐明了电机工作模态的激发过程;其次对电机结构进行了设计,确定了振子尺寸,组装了一台直线超声电机. 相似文献
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运载火箭贮箱壁板机铣装夹技术研究 总被引:1,自引:0,他引:1
为进一步提供运载能力,对新一代运载火箭提出了减重要求,其贮箱壁板加工工艺方法由机械铣切替代化学铣切。围绕某型号运载火箭的研制需求开展了贮箱壁板机铣装夹技术研究。通过对壁板的结构特点及加工工艺性分析,确定了"先弯后铣"的工艺方法。通过开展工艺试验,定位了引起产品超差的主要因素,分析了超差原因,制定了解决措施,引出了真空吸附装夹技术研究的需求,阐述了真空吸附装置的设计方案。结合真空吸附原理,进行了机铣过程切削力理论计算,确定了真空吸附系统的吸附力、吸附面积,优化了密封结构设计,实现了柔性装夹。最终通过合格产品的试制,验证了真空吸附装夹装置的有效性。 相似文献
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In a recent paper, the Ritz method with simple algebraic polynomials as trial functions was used to obtain an eigenvalue equation for the free vibration of a class of homogeneous solids with cavities. The method presented is here extended to the study of a class of non-homogeneous solids, in which each solid is composed of a number of isotropic layers with different material properties. The Cartesian coordinate system is used to describe the geometry of the solid which is modelled by means of a segment bounded by the yz, zx and xy orthogonal coordinate planes and by two curved surfaces which are defined by fairly general polynomial expressions in the coordinates x, y and z. The surface representing the interface between two material layers in the solid is also described by a polynomial expression in the coordinates x, y and z. In order to demonstrate the accuracy of the approach, natural frequencies are given for both a two- and three-layered spherical shell and for a homogeneous hollow cylinder, as computed using the present approach, and are compared with those obtained using an exact solution. Results are then given for a number of two- and three-layered cylinders and, to demonstrate the versatility of the approach, natural frequencies are given for a five-layered cantilevered beam with a central circular hole as well as for a number of composite solids of more general shape. 相似文献
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对某型卫星转播车方舱的装载要求进行分析,结果证明,必须对方舱舱体的质量进行严格的控制,在不影响整舱强度的条件下,采取各种方法,尽量将方舱质量减到最轻。本文从方舱的舱板、舱门及孔口和舱体拼装等几个方面,对可能采取的减轻质量的方法进行了分析,对方舱所用型材、拼装结构和涂胶量进行优化、减重分析和处理,结果可满足对整车的功能性要求和质量限制。 相似文献
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描述了用于K型热电偶回路中的镍铬接触对在电连接器的振动过程中发现接触电阻变大的失效现象,从接触电阻的理论构成和失效接触对的实物状态进行原因分析,通过更换绝缘体材料、固定接触对及更换接触对等方式进行试验验证,确定主要原因。针对分析结果,通过降低表面粗糙度、提高接触压力、涂覆固体膜润滑剂和调整接触对固定机构等方式,解决了镍铬接触对在振动过程中的接触电阻失效问题。通过一系列的试验,总结了避免镍铬接触对失效的关键措施。 相似文献
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Elisa do Carmo Agostini Balbinot Marta Fvaro Costa Cesrio Pereira Jovito Adiel Skupien Carlos Eduardo Agostini Balbinot Grazielli da Rocha Sergio Vieira 《Microscopy research and technique》2019,82(11):1953-1961
The objective of this study was to evaluate and correlate light transmittance (T), initial degree of conversion (IDC), and degree of conversion after 24 hr (DC24) for 22 composite resins (CR) for enamel and dentin use. The transmittance (n = 10) was measured with a spectrometer at a wavelength of 468.14 nm. The degree of conversion (DC; n = 5) was measured with Fourier Transform Near‐Infrared Spectroscopy before polymerization, immediately after photoactivation, and 24 hr after photoactivation. Both sets of values are provided as percentages. ANOVA and Games‐Howell (α = 5%) tests showed that Filtek Supreme Ultra gave the highest T values of all enamel CRs, while Esthet‐X HD presented the lowest. Meanwhile, Venus diamond gave the highest values of all dentin CRs, while Esthet‐X HD gave the lowest. For IDC and DC24, ANOVA showed differences between individual CRs and the two CR types (p < .0001). Despite the limitations of this study, it can be concluded that there was no correlation between T and either IDC or DC24 (p > .05); however, IDC and DC24 were strongly correlated (p < .05) by Pearson's correlation. That being said, as a higher DC reflects better mechanical properties, certain conclusions can be drawn about overall performance. The best IDC values were observed for the Opallis enamel resin and the Opallis and Premise dentin resins. Meanwhile, the best DC24 values were observed for the Opallis, Charisma, and Premise enamel resins and the Opallis and Premise dentin resins. Degree of conversion and light transmittance showed differences between composite resin types (enamel and dentin) and brands. It is important to know at the moment of composite choice taking into account mechanical and optical properties. 相似文献
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介绍了挖掘机液压系统的功率参数与流量控制机理,从液压系统的功率角度分析了液压挖掘机的功率控制方式,从挖掘机负流量液压系统与正流量液压系统的工作原理方面分析了其控制性能及优缺点,并总结了挖掘机负流量液压系统与正流量液压系统的技术价值、应用场合及改善方向。 相似文献
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