重型数控落地铣镗床床身安装工艺方法研究

针对重型数控落地铣镗床床身安装调整的难度,介绍了床身安装、粗调、精调的工艺方法及注意事项。     

FBC系列数控落地铣镗床滑枕加工技术

FBC系列数控落地铣镗床滑枕是万能重大型精密数控机床主要部件。FBC200r型数控落地铣镗床,其镗轴直径200mm,铣轴直径320mm,方滑枕尺寸520mm×580mm×3895mm,滑枕最大行程Z=1200mm,镗轴最大行程形：1200mm。滑枕体四面为静压导轨面,     

重型数控落地铣镗床床身导轨副应用恒压闭式静压导轨的研究

介绍了静压导轨的特点,以及将恒压闭式静压导轨技术应用于重型数控落地铣镗床床身导轨副的设计过程。     

数控落地铣镗床主轴箱设计

通过对主轴箱垂向Y轴行程8 m的数控落地铣镗床使用静压蜗杆、蜗母条传动结构,提高了Y轴的工作精度和使用寿命,解决了有效加工高度大于7 m的矿山机械转筒零件加工难的问题。     

数控落地铣镗床主轴箱平衡补偿系统及其调试

介绍了一项实用的关键技术-数控落地铣镗床主轴箱平衡补偿系统及其调试方法。GIMAX系列高精度数控落地铣镗床是我公司在引进法国FOREST-LINE公司先进技术的基础上开发的新产品。数控落地铣镗床具有龙门式机床无法替代的工艺适用范围：开放的工作区特别适用于超大型、不规则零件的加工；滑枕镗轴机构可满足大直径深孔类零件的高精度加工。该机床采用了先进的静压镗轴技术和主轴箱平衡补偿技术。静压镗轴兼有静压轴承和静压导轨之作用，将传统的机械式镗轴一铣轴多层组合结构简化为单一的镗轴，并具有如下优点：     

陶瓷刀片精铣钢导轨──大型焊接结构件的精铣加工

我厂与联邦德国席士公司合作生产最新设计的FB260型数控落地铣镗床,其床身、立柱是大型焊接结构钢导轨。焊接件轮廓尺寸大、形状复杂、精度要求高,我们采用陶瓷刀片精铣效果很好。现将加工情况介绍如下: 1.加工零件的技术要求 图1所示的床身由两段组成。床身“I”的尺寸为9000× 2300 × 600mm,重18 t,床身“ Ⅱ”为8000× 2300 × 600mm,重16 t,两段床身总长为17000mm。席士原图的导轨表面粗糙度为Ra0.4m(9)。精度要求:直线度允差每米为0.015mm;全长为0.07mm;两导轨平行度允差全长0.015/1000;导轨面与压板面的平行度允差全长0.02mm。材料…     

重型数控落地铣镗床方滑枕移动精度补偿系统研究

研究了重型数控落地铣镗床方滑枕移动精度补偿系统的关键技术,介绍了采用全数字式电液比例减压阀控制液压系统的压力变化实现非线性补偿方式,以及重型数控落地铣镗床方滑枕移动精度补偿系统的关键结构。     

数控内圆磨床磨削锥外圆与大端面

1．零件分析图 1所示零件是我公司生产的重型数控落地铣镗床的关键零件之一——伸长铣头。落地铣镗床在使用铣头体加工零件时,零件的质量好坏与铣头精度有很大的关系,而该零件作为铣头体的关键件,自然图样要求各项精度都必须严格保证。     

重型数控落地铣镗床滑枕部件精度调整方法的研究

主要介绍了重型数控落地铣镗床滑枕及主轴相关精度的调整结构及方法。     

超重型数控落地铣镗床滑枕挠曲变形补偿研究

针对超重型数控落地铣镗床大行程滑枕的变形补偿难题,提出了一种理论分析、数值计算与实验研究相结合的方法,利用有限元分析方法找出滑枕挠曲变形分布规律和变形与滑枕行程间的关系,通过理论分析确定拉杆补偿力的初算值,结合有限元分析方法得到了补偿力与滑枕行程关系曲线。理论与实验结果对比表明,该方法较准确地预测了超重型数控落地铣镗床滑枕挠曲变形分布情况,满足了机床滑枕挠曲变形的补偿要求。     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...     

End-to-End Multiview Gesture Recognition for Autonomous Car Parking System

The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods....     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

ANGULAR DISTORTION ALLOWABLE VALUE AND ASSESS METHOD OF WELD ON COKE TOWER

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.