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液压软管卷盘的控制策略及安全监控系统设计 总被引:1,自引:0,他引:1
液压软管卷盘是为地下连续墙施工装置的液压系统提供液压油源的重要部件,软管在卷盘马达作用下随着施工装置的动作同步收放.通过对软管收放过程的分析和计算,得到驱动卷盘所需的扭矩和缠绕角度的关系,指导设计软管收放系统的智能控制策略.基于此策略设计液压软管卷盘的安全监控系统,经现场试验效果良好. 相似文献
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对国内外软管铺设技术及装备进行了分析。为了能够在更深的海域进行软管铺设,提出了一种垂直式铺设的软管铺设塔系统方案。在铺设塔上搭载张紧器、AR绞车等核心部件,在进行软管铺设过程中起到更好的辅助作用。根据软管铺设的实际需求,确定了软管铺设塔系统的设计参数;对软管铺设塔系统的各个部件进行了详细设计,并介绍了软管铺设的工作原理和过程;结合实际工作海况的要求,基于有限元软件对铺设塔架以及各关键部件进行了强度校核。有限元分析的结果表明,该铺设塔系统的设计满足软管铺设的需求,验证了其结构设计的正确性和可靠性。 相似文献
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任何液压系统都存在着软管材质与系统用油的匹配问题。如匹配不当,会导致整个系统产生故障。如:石油基液压油会很快地使其含乙烯、丙烯、二烯材质的液压软管产生质变,随之软管损坏,通路阻塞,设备发生故障,生产率降低,维修费用上升等,这些都是液压软管材质与系统用油匹配不当的结果。本文将帮助系统设计者或使用者选择液压软管与系统用油之间的匹配关系,以保证液压系统的可靠性及其寿命。 相似文献
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介绍了双软管隔膜泵液压系统及双软管隔膜结构,过压保护、驱动液压力监测、液压油泄漏补偿等保护系统的设计,当液压缸出现超压时过压保护系统对其进行卸压,同时保护了软管隔膜、行程齿轮箱以及驱动电动机,防止其过载。结果表明该保护与监测系统提高了液压系统的安全可靠性,延长了双软管隔膜的使用寿命,满足液压隔膜泵的安全、稳定及长周期运行要求。 相似文献
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现代大型液压系统中,几乎都少不了使用软管作为活动和振动部位的柔性连接件。就软管而言,根据系统压力、温度的不同,有金属软管、氟塑料软管和橡胶软管之分。不管那种软管,在结构上都是由管体、补强层和端接头组成。其中承压能力是由补强层的材质和合理的工艺设计来保证。在软管标准规范中,都有最小弯曲半径的限制。在美国军用标准MIL-H-5440飞机Ⅰ型和Ⅱ型液压系统设计和安装要求规范中,也明确“软管组件的最小弯曲半径、取决于软管的尺寸和安装后所受弯曲的范围,软管的最小弯曲半径必须按适用的软管规 相似文献
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Cadmium, zinc, selenium, and copper were administered, singly or in combination, orally or subcutaneously. Experiment I included 32 calves of both sexes; six received Cd (two groups), Zn, Cd, and Zn, and Cd and Se (two groups) and one group was a control. In Experiment II (21 bulls), three were given Cd, Cd, and Cu, and Cd and Zn, respectively, and one group was a control. For light microscopy, in Experiment I the highest amounts of silver granules were present in the samples of liver, small intestine, and vesicular gland of all the exposed groups; in Experiment II the most affected organs were liver, kidney, and small intestine. For electron microscopy, in Experiment I, after administration of Cd and Zn, the highest amounts of granules were seen in the cytoplasm of hepatocytes and cells of the proximal and distal renal tubules and the lowest amounts were found in glandular cells of the pancreas. Administration of Cd and Se resulted in the presence of large numbers of granules in the nuclei and nucleoli of spermatogonies. In Experiment II, ingestion of Cd and Zn in feed led to the appearance of highest amounts of granules in the nucleoli, nuclei, and cytoplasm of cells in testes, kidneys, and pancreas. Following Cd intake, the highest accumulation of granules was observed in the nucleoli of hepatocytes and cells of the proximal and distal renal tubules. Combined Cd and Cu produced the highest number of granules in cells of the proximal and distal renal tubules and in the nucleoli and nuclei of germinal epithelium. 相似文献
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Aiming at providing with high-load capability in active vibration control of large-scale rotor system, a new type of active actuator to simultaneously reduce the dangers of low frequency flexural and torsional vibrations is designed. The actuator employs electro-hydraulic system and can provide a high and circumferential load. To initialize new research, the characteristics of various kinds of active actuators to control rotor shaft vibration are briefly introduced. The purpose of this paper is to introduce the preliminary results via presenting the structure, functions and operating principles, in particular, the working process of the electro-hydraulic system of the new actuator which includes a set of high speed electromagnetic valves and a series of sloping cone-shaped openings, and presenting the transmission relationships among the control parameters from control signals into the valves to active load onto shaft. The course of the work is dynamic, and a series of spatial forces and moments are put on the shaft to get an external resultant force to reduce excitations that induce vibration of shafts. By checking states of vibration, the actuator can control the impulse width and the interval of injection time for applying different control force to a vibration shaft in two circumference directions through the regulating action of a set of combination directional control valves. The results from simulating analysis and experiment show evidence of that this design can satisfy the case of active process of decreasing of flexural and torsional vibrations. 相似文献
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软体足式机器人驱动、建模与仿真研究综述 总被引:1,自引:1,他引:0
软体足式机器人因其优越的移动性能及面对复杂地形的通过能力受到越来越多研究者的关注。由于受到材料性质、驱动方法及制造工艺等多方面的限制,如何实现软体足式机器人的创新结构设计,提升软体机器人的运动速度和负载能力是目前亟待解决的问题之一。综述从仿生结构与驱动方法的角度对目前软体足式机器人的研究发展进行了系统阐述。由于软体机器人多为连续变形结构,加之软材料的物理非线性和软结构变形的几何非线性,力学建模与仿真一直是软体机器人研究领域的瓶颈。梳理了目前软体机器人的主要建模理论,总结了软体机械臂的建模与控制方法,进一步将其拓展到软体足式机器人的系统建模中。介绍了传统商业软件的应用与物理仿真引擎开发的进展,分析了软体机器人虚拟仿真的主要方法,展望了软体足式机器人的应用场景与未来研究方向。 相似文献
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以德士古气化炉耐火砖的内壁蚀损检测设备为基础,对采集到的点云数据做了进一步处理.通过对数据的筛选和剔除,实现了数据点的平滑降噪细化和精简.然后利用点云对整、网格划分和分色显示等方法,最终完成了内壁腐蚀情况的三维建模.重点讨论了点云数据的预处理及后处理的方法,并根据内壁耐火砖的腐蚀阈值,提出了一种气化炉内壁腐蚀区域的识别与分割方法.对耐火砖的腐蚀分析、气化炉的生产与维修提供了可靠依据,并在工程应用中获得了一致认可. 相似文献
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缩口扩口复合成型工艺研究与应用 总被引:1,自引:0,他引:1
针对铁路车辆罐车零件锥管缩口、扩口的成型特点,用冲压成型缩口、扩口的力学分析及变形原理进行工艺计算与研究,找出该零件废品率高的原因。通过改进工艺毛坯(钢管)的外径与壁厚尺寸,用冲压成型缩口、扩口工艺理论及图表进行论证分析,并进行试制,取得了较好的效果。 相似文献
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The role of mass spectrometry to probe characteristics of the influenza virus, and vaccine and antiviral drugs that target the virus, are reviewed. Genetic and proteomic approaches have been applied which incorporate high resolution mass spectrometry and mass mapping to genotype the virus and establish its evolution in terms of the primary structure of the surface protein antigens. A mass spectrometric immunoassay has been developed and applied to assess the structure and antigenicity of the virus in terms of the hemagglutinin antigen. The quantitation of the hemagglutinin antigen in vaccine preparations has also been conducted that is of importance to their efficacy. Finally, the characterization and quantitation of antiviral drugs against the virus, and their metabolites, have been monitored in blood, serum, and urine. The combined approaches demonstrate the strengths of modern mass spectrometric methods for the characterization of this killer virus. [This article was published online 10 September 2008. An error was subsequently identified. This notice is included in the online and print versions to indicate that both have been corrected 7 November 2008.] 相似文献
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为了进一步探索和研究气浮静压润滑支承机理及气浮静压导轨承载性能,提出并研制了一种具有气浮静压润滑支承的精密二维运动平台。结合气浮静压导轨的物理模型建立了其笛卡儿坐标系下的控制方程,采用有限差分方法和流量平衡原理对其控制方程进行了离散差分推导,运用超松弛迭代以及二分快速寻找收敛区间法对其承载性能进行数值计算并开展了实验研究。结果表明:气浮静压导轨承载性能受节流器类型的影响比较显著,多节流孔节流器的承载性能明显优于单节流孔节流器;供气压力对气浮静压导轨承载性能影响显著,供气压力越高其承载性能越强;同等条件下气浮静压导轨组合形式承载性能均优于单独形式承载性能;气浮静压导轨的承载性能实验测试结果和数值计算结果具有较好的一致性,验证了数值计算的有效性。相关研究对推动和促进气浮静压轴承和导轨在精密运动机构和测量设备的研究和工程应用具有较好的借鉴和指导意义。 相似文献
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针对高方平筛和其上固结的柔性吊杆组成的动力学系统,进行了刚柔耦合的动力学建模和振动模态分析。将筛体—偏重块系统和吊杆分别作为刚体和弹性的可变形体,建立了筛体稳态圆振动方程和吊杆悬臂梁力学模型,总结出系统固有频率的计算方法。在此基础上,采用有限元方法对系统进行了模态计算和动力学响应分析。结果表明,理论模型能够很好地反映筛体与吊杆之间的动力学耦合关系;以理论分析为基础的载荷和边界条件的设置,使有限元仿真结果较准确地模拟了系统实际的振动特性。 相似文献
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覆膜铁是金属包装领域的新型复合材料。成品覆膜铁的界面结合强度和水透性取决于覆膜过程中高聚物薄膜熔融层的厚度和流动铺展行为。但覆膜过程复杂而迅速,且受钢板表面微观形貌影响,熔融层膜厚及其流动铺展行为难以精细调控。针对此,基于分形理论表征与重构基板带钢表面微观形貌;基于广义Maxwell模型试验建立聚合物膜的黏弹性本构关系;建立了考虑基板带钢表面微观形貌的覆膜过程有限元仿真模型,并试验验证了模型的准确性。研究表明,熔融层膜厚主要受基板带钢初始预热温度影响,界面填充率则主要受覆膜辊压力影响。高聚物膜熔融层厚度和界面填充率随基板带钢粗糙度降低以及基板带钢和覆膜辊初始预热温度增加而增加,且辊压力增加也导致界面填充率增加。这些规律被定量化描述,为精细化调控熔融层膜厚及其流动铺展行为提供了理论依据。 相似文献