不锈钢精加工正角刀片槽型的设计

通过分析两种进口精车不锈钢断屑槽刀片,对该正角刀片的槽型进行测绘并进行切削对比试验,系统分析其槽型结构。结果表明:刀片的前角、刃宽和复合断屑台在加工不锈钢时对断屑起关键作用。通过试验、综合分析和验证后,确定不锈钢精加工正角刀片槽型最优结构为5°单前角、0刃宽和复合断屑台。     

带减摩槽刀片切削机理的研究

对带减摩槽刀片的切削机理进行了理论研究,考察了减摩槽对主切削力（ＦＺ）以及切削变形和断屑性能的影响,在此基础上得出三维断屑槽设计的一些有益结论,并通过平前刀面刀片和带减摩槽刀片的对比切削试验验证了这些结论,最后据此设计了一种新型断屑槽。     

带新形断屑槽的车刀

切削时切下的切屑主要是靠与主切削刃平行或成7—15°角的各种断屑槽和断屑台进行断屑的,这种刀具在重磨对断屑槽会被磨去,并需重新加工,这就缩短了刀具的使用寿命(因为在一次重磨内就磨掉刀片的较大部分)和     

圆弧刃刀片的断屑性能

通过对新设计三种直径圆弧刃刀片的断屑槽型进行断屑性能的试验研究，得出了在不同切削条件下的断屑特点和有效断屑范围。     

刀片断屑槽型的测绘

<正> 我们常看到有些机床上用的刀具,切削轻快,导屑稳定或断屑良好,迫切希望知道其特点、断屑槽型。经测绘仿制后,扩大使用。新设计的刀片经过生产验证,能达到断屑等予期效果。据此,设计压模,定型生产。制造压模时,也要检查其形状是否符合图纸要求。经过分析研究和生产验证,认为可取的国外刀片,有复制生产的必要,也应测绘刀片图形。做断屑比较试验,首先应该知道刀片的几何参数与断屑槽型。总之,测绘工作对上述各     

两种新型断屑装置

在车加工时有两种主要断屑方法：在切削刀片上制作断屑槽和附加断屑器。第一种方法有许多缺点，因为断屑槽将降低切削刀片的强度，在切削时引起刀片振动，从而加速车刀的磨损，显著降低加工质量。此外，若切削用量和断屑槽的形状选择不当，则在刀片上会出现积屑瘤，从而降低耐磨涂层刀片的切削效果，急剧降低断屑的稳定性。下面介绍两种新型断屑装置，可有效断屑和提高加工质量。带回转断屑器的车刀图１所示为带回转断屑器的车刀。在刀夹１内的销钉２上装有切削刀片４和支承刀片３，以及可在销钉上回转的断屑器５，见图１（a）。断屑器是一…     

复杂槽型数控车刀片断屑预报系统的研究

针对数控车削加工过程中切屑折断难以预测问题,依据切屑折断界限理论建立了极限进给量和极限切削深度的预报数学模型:以上述数学模型为核心,开发了复杂槽型数控车刀片的断屑预报系统.为了验证预报结果的准确性,选取了典型的复杂断屑槽型车刀片切削45钢的断屑试验结果与预报结果进行了对比,对比结果显示二者基本一致,从而证明断屑预报结果的准确性和断屑预报系统具有一定的实用性.     

基于人工神经网络的可转位刀片3维断屑槽的建模和预测

本文讨论了用人工神经网络对可转位刀片 3维断屑槽进行建模和预测的问题 ,提出了一种 3维槽型几何特征参数的提取方法 ,在此基础上建立了预测 3维断屑槽断屑范围的人工神经网络模型。试验结果表明 ,该模型的预测准确率达95 %以上     

硬质合金刀片嵌入式辅助断屑器的设计

为了扩大硬质合金刀片的断屑范围,结合硬质合金刀片三维槽型的结构特征和刀片安装方式,设计并制作了一种嵌入式辅助断屑器。进行了铝合金切削实验,观察了切屑形貌,并分析了切屑折断机理。实验结果表明,未安装嵌入式辅助断屑器时,硬质合金刀片在小切深下可以实现断屑;但在大切深时,产生长螺卷屑,硬质合金刀片的断屑效果变差。安装嵌入式辅助断屑器后,在大切深时,硬质合金刀片产生了C形屑。嵌入式辅助断屑器的反屑面增加了断屑台的高度和角度,进一步减小了切屑的卷曲半径,促进了切屑的折断。安装了嵌入式辅助断屑器的刀片具有较高的断屑率,扩大了硬质合金刀片的断屑范围。     

伊斯卡推出新型断屑槽及IC5400牌号

正近日,伊斯卡为切断刀片新增了适用于不锈钢及难加工材料的切断和切槽加工的LF、LFT和MF三种断屑槽,结合新的IC5400硬质合金牌号,为不锈钢的切断及切槽加工提供了高效的解决方案。新型LF断屑槽设计结合了正前角、断屑倾斜面及锋利切削刃,最终收获低的切削力,并对积屑瘤的形成起到抑制作用。另外,能有效地使切屑变窄,排屑更流畅,被加工表面质量更高。LFT断屑槽基于LF断屑槽而设计,仅在切削刃处做了T-land负倒棱处理,从而使得切削刃及刀尖圆角具有抗崩刃性,更耐用。相比于带LF断屑槽的刀片,带LFT断屑槽的刀片能实现更高的进给速度。MF断屑槽基于C形断屑槽设计,增加了较高的断屑台,对切削刃     

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.     

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.     

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....     

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.