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1.
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   

2.
对冷床上卸钢系统和四辊轧机开卷机液压系统存在的问题进行了分析,找出了产生问题的原因,并对原液压系统进行了改造,经改造后的系统,减少了油液的泄漏,提高了系统的稳定性,减小了维修强度,降低了维修成本,提高了系统的工作效率.  相似文献   

3.
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   

4.
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   

5.
基于有限元分析方法的高速电主轴热态特性研究   总被引:5,自引:0,他引:5  
介绍了高速电主轴的特点,分析了高速电主轴单元的热变形机理与散热机制。建立了某型高速电主轴热态特性有限元分析模型,利用ANSYS进行了稳态/瞬态温度场及热-结构耦合场分析,并利用分布加载瞬态热分析模拟了机床一天中的实际工作情况,得到了电主轴的温度场变化情况,为有效控制电主轴的温升提供了理论依据。在分析结果的基础上,提出了改善电主轴热态特性的措施,为电主轴冷却结构设计提供了参考。  相似文献   

6.
柏青  钟康民 《机械制造》2007,45(6):63-64
介绍了一种新型的基于直线电机驱动的复合传动增压装置,对系统的工作原理进行了分析,并给出了工作原理图,对系统的输出流量与输出力进行了分析计算,给出了相应的计算式.该装置实现了液压油的封闭式循环,减轻了油液对环境的污染,技术功能较为完善,工作效率显著提高.  相似文献   

7.
分析了曲轴的机械加工要求和特点,设计了一种一次装夹的组合钻床,给出了总体设计结构和各部件的组成;对钻削动力头进行了动力分析和切削分析,详细推导了切削力、切削扭矩和切削功率的计算公式,确定了钻削动力头的功率范围;最后分析了钻削主轴结构及夹具定位系统,给出了钻孔主轴的设计规范及直径的计算公式,并阐速了夹具系统总体设计上的几点考虑.  相似文献   

8.
叙述了液压系统中颗粒杂质对元件的危害,简述了太钢热连轧厂1549 mm轧机改造后采用了大量液压技术,围绕液压系统油品清洁度制定了有效的管理制度,取得了较好的效果.  相似文献   

9.
一面两孔的定位分析与计算   总被引:1,自引:0,他引:1  
阐述了一面两孔的概念,分析了定位元件所限制的自由度数.以及处理过定位的方法,介绍了两种一面两孔定位方式,比较了两者的优缺点.侧重分析了后一种定位方式,并给出了计算实例.  相似文献   

10.
闫伟  尹松  杜劲 《机械工程师》2007,(3):111-112
简述了抽油机的发展历程,分析了各阶段抽油机的特点及存在的问题.同时结合现阶段油田生产的特点,分析了节能抽油机的发展趋势.从一个新的角度分析了抽油机节能改进的方向.提出了"一机双井"的工作模式,做了简单的定性分析.  相似文献   

11.
The effect of the prebuckling in-plane deformations on the elastic flexural-torsional buckling of laterally fixed circular arches is studied in this paper. The finite strains and the energy equation for the flexural-torsional buckling of arches have been derived based on an accurate orthogonal rotation matrix. A closed form solution for the elastic flexural-torsional buckling resistance of laterally fixed arches in uniform bending, including the effects of the prebuckling deformations, is obtained. It is found that the notion that the prebuckling deformations increase the flexural-torsional buckling moment of an arch or of a beam is not necessarily correct for a laterally fixed arch or beam in uniform bending, in deference to a laterally pinned arch. When a laterally fixed arch is subjected to positive uniform bending, the effects of the prebuckling deformations decrease the buckling moment, and the reduction of the buckling moment increases with an increase of the included angle and of the out-of-plane slenderness ratio of the arch. When a laterally fixed arch is subjected to negative uniform bending, the effects of the prebuckling deformations decrease the absolute value of its buckling moment when the included angle is very small, but increase the absolute value of the buckling moment when the included angle exceeds a certain value. The increase in the absolute value of the buckling moment increases with an increase of the included angle and of the out-of-plane slenderness ratio of the arch. When the ratio of the out-of-plane to the in-plane second moments of area of the cross-section is not small, both the reduction of the buckling moment of a laterally fixed arch in positive uniform bending and the increase of the buckling moment of a laterally fixed arch in negative uniform bending, are substantial.  相似文献   

12.
轿车门系统结构设计与优化是整车开发过程中的重要环节。车门的强度直接关系到整车在冲击、碰撞等载荷下的安全问题,车门结构静态强度的计算分析,在车门结构设计进程中非常重要。文中首先简要介绍了静态强度所涉及到的非线性有限元的基本理论,然后以某中高级轿车前车门为例,利用计算机辅助分析车门的静态强度,考虑变形的非线性因素,通过对车门的非线性有限元求解来分析车门强度,由计算所得到的车门强度性能指标来指导车门的结构设计。  相似文献   

13.
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   

14.
During plastic process,the material flow is strongly influenced by the contact area between deformed workpiece and die.In rolling process,difference of roll diameter makes the contact area between roll and deformed tape different,which leads to different material flow and the distribution of powder density.A numerical modelling of the first rolling process for 61-filament high temperature superconducting tape is constructed and the influences of roll diameters on deformation behavior of the tape are discussed.It can be found that the BiSrCaCuO(BSCCO)powder in the center of the tape has higher relative density than those in the periphery of the tape during rolling process.With the increase of roll diameter,the length of the contact arc in the roll gap expands which lead to the in- creasing of transversal strain and the decreasing of the related longitudinal strain.It makes the value of longitudinal strain ratio decrease gradually,which decreases the possibility of occurrence of the transversal shear band,simultaneously it increases the risk of occurrence of longitudinal crack.  相似文献   

15.
基于生物质谱的蛋白质组学绝对定量方法研究进展   总被引:1,自引:0,他引:1  
曹冬  张养军  钱小红 《质谱学报》2008,29(3):185-191
蛋白质组学定量方法包括相对定量和绝对定量两部分。相对定量蛋白质组学(也称比较蛋白质组学)是指对不同生理病理状态下细胞、组织或体液蛋白质表达量的相对变化进行比较分析;绝对定量蛋白质组学是测定细胞、组织或体液蛋白质组中每种蛋白质的绝对量或浓度。目前蛋白质组学的绝对定量方法主要有基于内标法的蛋白质组学绝对定量方法和基于质谱数据统计分析的非标记方法。蛋白质组学定量的信息可以帮助了解蛋白质在相互作用网络中所起的作用;通过对临床生物标记物绝对量的分析,可以帮助直观地判断疾病的发生和发展过程,这对于临床诊断和疾病治疗都具有现实的指导意义。  相似文献   

16.
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   

17.
The effect of the molecular structure of basic nitrogen compounds on the lubricating properties of sulphurised olefin has been investigated using a Timken tester. X-ray Photoelectron Spectroscopy (XPS) and Energy Dispersive X-ray Analysis (EDAX) were used to study the chemical states of sulphur and nitrogen on the rubbed surfaces and the reaction rates of sulphur and iron separately. It was found that the antiwear and friction reduction properties of sulphurised olefin are greatly influenced by the different molecular structures of the basic nitrogen compounds. A composite additive package containing basic nitrogen compounds with sulphurised olefin can produce either synergistic or antagonistic effects, due to the influence of the different molecular structures of the basic nitrogen compounds. XPS analysis revealed that a tribochemical protective film containing nitrogen and sulphur was formed on the rubbed surface. EDAX analysis indicated that the reaction rates between elemental sulphur and iron were influenced by the different molecular structures of the basic nitrogen compounds. It was found that the apparent reaction rates of elemental sulphur and iron are related to the tribological characteristics of the additive package.  相似文献   

18.
A newly found phenomenon of carved driving wheels of a rear-wheel-drive tractor used in an airport is discussed. The circum of every driving wheel is damaged at three regions,which distribute regularly and uniformly. Everyday,the tractor tows a trailer which are times heavier than the tractor,and moves on the same road in the airport. The phenomenon is explained by the torsional self-excited vibration system of the powertrain. The simplified torsional vibration system is discribed by a 2-order ordinary differential equation,which has a limit circle. Experiments and numerical simulations show the followings: Because of the heavy trailer,the slip ratio of the tractor’s driving wheels is very large. Therefore,there is severe torsional self-excited vibration in the tractor’s drivetrain,and the self-excited vibration results in severe and regular fluctuations of the rear wheel’s velocity. The severe fluctuations in velocity fastens the damage of the driving wheels. At the same time,the time interval in which an arbitrary point in the circum of the driving wheel contacts with the road twice is two times more than the period of the torsional self-excited vibration,and this times explained the existence of three damaged regions. At last,it points out that the phenomenon can be avoided when the torsional damping is large enough.  相似文献   

19.
A graph as the new engineering method for estimate the safety of bulging deformation of coke tower is proposed. Through stresses analysis of circumferential weld of coke tower and comparing the stresses produced by pressure with heat stress of steady state, residual stress, bending stress produced by both itself weight and wind loads, it showed that the stresses produced by pressure on the angle distortion are the main factor of equivalent stress of the combined stress. After comparing four kinds of stress controlling conditions, the relation to stress with depth of angular distortion, grade of curvature of angular distortion and half of region of angular distortion has been inferred. Graph of deformation allowable value of coke tower for different condition by angular distortion and half of region of angular distortion has been plotted. The five steps for its engineering use have been explained. The lighter the grade of curvature is, the larger of bulge allowance, may be, and the bigger of depth of angular distortion may pose too. For the coke tower with a popular structure of Dg 5 400 mm×28 mm, the result by graph is nearly more than the result of two formulas formed by other research, the error is less than 7.0%. But, the graph can be easily applied to different size of angular distortion.  相似文献   

20.
利用可见光谱数字化分析系统将铝合金中Fe元素Fe526.95nm分析谱线组谱图转变为数字化的电子谱图,使用计算机自动分析代替人眼视觉判断,解决谱图的量化分析和记录难题。对4种不同Fe元素含量的铝合金样品进行数字化分析测定,探索选用Fe526.95nm谱线作为分析谱线,选用Cu529.25nm谱线作为比较谱线进行定量测定的方法,数据显示分析谱线和比较谱线的强度比值与Fe元素含量成正比关系。研究数字化系统指导视场定位和谱线辨别的途径,降低可见光谱分析的技术难度并提高快速分析的可靠性。结果表明,数字化技术保持快速分析特点的同时可以达到定量分析目的,能够有效解决铝合金中Fe元素的快速定量分析及材料牌号鉴别问题。  相似文献   

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