国内挖掘装载机的发展状况及发展趋势

简要介绍了挖掘装载机的结构及新时期国内装载机的发展状况,并对挖掘装载机的发展提出一些建议,为装载机的进一步改进提供依据.     

挖掘装载机的发展现状、趋势及研制思路

从国内外挖掘装载机的发展、主要生产厂家及其市场情况阐述了挖掘装载机目前的发展状况及发展趋势，为提高我国挖掘装载产品的可靠性、整体生产水平及市场占有率提供了一些新的研制方向。     

国内外挖掘装载机发展综述

本文主要论述国内外挖掘装载机（谷称两头忙）的发展及产销状况，国内外部分挖掘装载机产品简介及其今后发展趋势。     

挖掘装载机市场现状与发展趋势

正挖掘装载机分类按照底盘结构来分,挖掘装载机可分为铰接式和整体式,如图1、图2所示。铰接式挖掘装载机是在装载机基础上后端加装挖掘工作装置。由于其底盘结构、传动件等可以借用装载机产品,其性价比高,但其整机长度、高度等相对大些,机身质量较大,制约了其向更高层次发展,属于中低档机型。整体式挖掘装载机兼顾装载和挖掘性能,其设计更为合理和紧凑、     

两头忙大比武 凯斯580N、JCB3CX-Eco、柳工CLG766A挖掘装载机评测

正挖掘装载机俗称"两头忙",属于小型多功能工程机械的一种,一般在大工程完成后的小工程中使用。它可配多种工作装置及属具,进行挖掘、铲装、路面破碎、平整场地、开挖沟渠、铺设管道等多种作业。虽然我国挖掘装载机的发展遇到了种种问题,但近年来,随着用户需求的不断变化,挖掘装载机的适用范围也在逐步拓宽。其灵活的工作空间、便捷的运输方式这些与生俱来的优势慢慢被人们所重视。本期我们挑选3款国内市场主流的7~8t级挖掘装载机进行综合对比评测,希望能为读者选购提供参考。     

凯斯695 SUPER M型挖掘装载机

2002年11月凯斯家族的又一新产品——695SUPER M型挖掘装载机在中国亮相。凯斯这个最新的M系列挖掘装载机的推出,进一步巩固了其在挖掘装载机领域内的领先地位。 695 SUPER M型挖掘装载机提供3种转向模式,前轮转向、四轮转向及“蟹行”模式,此功能在很大范围内提高了该设备的性能。695 SU-     

国内挖掘装载机市场分析

挖掘装载机作为一种多功能多用途的工程机械产品,多年来一直在国际工程机械市场中占有相当大的份额.根据2003年的统计数据,挖掘装载机在北美、欧洲、日本等国际主流工程机械市场中是产销量最大的主要工程机械品种之一,其销量超过了轮式装载机及6 t以上挖掘机.而在中国工程机械市场上,挖掘装载机被俗称为"两头忙",几乎还是一个只闻其声不见其影的新事物,在各类工程施工的场地上还鲜见其踪影,其销量与装载机、挖掘机相比,几乎可以忽略不计.如果中国工程机械市场也会按照欧美规律进行演变的话,那么中国挖掘装载机的市场潜力可谓巨大.     

制动助力器在挖掘装载机上的应用

挖掘装载机机动灵活,广泛用于道路建设、电缆铺设以及自来水、污水、热力管网建设和维修。制动助力器作为挖掘装载机制动系统的核心零部件,关系到其行驶的安全性和可靠性。本文以美国卡莱制动与摩擦材料公司(CBF)Booster系列制动助力器为例,介绍挖掘装载机制动助力器的安装及应用技术。     

挖掘装载机司机防护装置试验方法

在现行的土方机械司机室防护装置的实验方法的基础上提出了挖掘装载机司机室防护装置在落物保护方面的试验项目及相应的试验方法。该试验方法结合了装载机及液压挖掘机落物保护装置的试验方法,试验结果真实反应挖掘装载机在作业过程中对可能出现的落物危险的防护作用。     

国内外挖掘装载机发展综述

国外工业发达国家在80年代先后都积极开发研制挖掘装载机。意大利菲亚特阿利斯公司于1981年试制成功FB7型挖掘装载机样机,后来又发展到带有纵向或横向挖掘装置的“B”系列,均为四轮驱动,发动机功率从51.5kW(7O马力)提高到58.8kw(8O马力),并对后置挖掘装置进行了重新设计。之后Veneries公司又决定为MFI工业公司在原西德、法国和英国生产铰接式挖掘装载机。美国卡特彼勒公司于1986年3月将第一台挖掘装     

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.     

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。     

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....     

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.     

Limits of topographic measurement by the scanning tunnelling and atomic force microscopes

Parameters describing the topographic character of a surface (height, surface wavelength, slope and curvature) can be derived from equivalent sinusoidal profiles. The response of a surface-measuring instrument may be modelled in terms of instrument parameters such as stylus radius, and scanning range and resolution. The performance of the instrument may then be mapped as a zone in amplitude-wavelength (AW) space to show the sinusoidal profiles it is capable of measuring. In a first-order analysis the STM and AFM are considered as equivalent to contact-stylus instruments with a notional stylus radius equal to the tip radius plus the gap. Comparisons between different instruments and types of instrument are readily made by mapping in AW space. The error arising from convolution of the sinusoidal profile with that of the finite tip may be quantified and plotted as contours in AW space.