矿用地下铲运车驾驶室翻车保护结构的仿真与试验分析

根据某地下铲运车的驾驶室翻车保护结构(ROPS)型式,建立了非线性有限元模型,模拟了ROPS试验的侧向、垂向及纵向加载过程并得到3个方向的载荷-位移曲线,分析了其变形规律;同时对该模型进行ROPS试验测试。通过与试验结果进行对比,表明有限元分析方法能够较好的预测铲运车ROPS在承受各向载荷时的变形规律;分析了试验与有限元结果产生偏差的原因;指出了ROPS的结构特点及薄弱处,为该类铲运车ROPS的结构设计及优化提供了参考依据。     

矿用地下铲运机驾驶室ROPS的试验及有限元分析

以某地下铲运机驾驶室的翻车保护结构(ROPS)为研究对象,采用非线性有限元分析方法仿真了ROPS试验的侧向、垂向及纵向加载过程,得到各方向的载荷-位移曲线。根据国际标准ISO 3471:2008对该装置进行了测试,并与有限元分析结果进行了对比。结果表明,该有限元分析方法能够较合理地预测ROPS在各方向承载时的变形规律。此外,分析了试验结果与有限元分析结果之间偏差产生的原因,指出了该ROPS的相对薄弱处,为该类地下铲运机ROPS的结构设计及优化提供了依据。     

地下装载机司机室司机安全保护结构试验

随着人们对安全重视程度的增加,国内外地下装载机越来越多地配备了司机室司机安全保护结构,即落物保护结构(FOPS)或翻车保护结构(ROPS),并出现了严格的、强制性的国际和国内标准。针对地下装载机的司机室特殊结构,简略介绍了国内相关标准中有关地下装载机FOPS和ROPS的试验设备、试验条件、试验方法、试验结果分析与评估以及试验实例。     

旋挖钻机大三角变幅机构受力分析数学模型的建立

应用理论力学、弹塑性力学和液体的弹性模量等相关理论与知识,对旋挖钻机大三角变幅机构各铰接点受力进行分析并建立了数学模型,为机械设计工程师在设计选型、校核、有限元分析边界条件计算、有限元运算结果分析校核以及优化设计等方面提供了理论参考。     

ANSYS对钢筋混凝土结构弹塑性问题的仿真研究

讨论了弹塑性有限元理论和大型有限元软件ANSYS在钢筋混凝土结构中的应用,探讨了弹塑性有限元理论中的单元类型、材料本构关系和有限元模型的建立以及在ANSYS中的实现,对边界条件的处理、求解精度和加速解的收敛性等问题给出一些改进措施,最后通过与试验值比较,验证了ANSYS仿真结果的可靠性。     

基于SolidWorks Simulation的矿用隔爆箱弹塑性力学分析

针对现有矿用隔爆箱设计方法的适用范围小、安全裕度过大、浪费材料和缺乏整体性理论分析等问题,采用弹塑性力学方法和SolidWorks Simulation有限元分析法对矿用隔爆箱的耐爆性、隔爆性分别进行静力学计算,并对两种计算结果进行对比。结果表明:SolidWorks Simulation有限元分析法计算结果与弹塑性力学方法计算结果非常接近,符合实际工况,解决了现有设计方法存在的问题,提出了隔爆箱改进方案,缩短了产品设计优化周期。     

有限元法及其在岩体力学中的应用(下)

五、非线性问题的有限元分析上面介绍了弹性平面问题的有限元解法,但是,将岩体看成弹性介质并不总是合理的。大家知道,岩体的性质很复杂,是一种高度变化的非连续和非均一的介质,其应力和应变的关系往往是非线性的,且有流变的特性,特别是岩体的力学性质往往受结构弱面的控制。对矿山岩体力学问题作深入的研究时,必须要考虑岩体力学的非线性问题。目前,国内外都在对岩体力学的非线性有限元分析进行广泛的研究,对解决诸如塑性、弹塑性、     

浅埋偏压隧道岩土体参数的位移正演反分析

以某浅埋偏压小净距隧道先行洞施工监测为工程依托,根据正交设计思想,确立实验方案,结合弹塑性非线性有限元计算构造训练样本,借助BP神经网络的超强非线性映射能力对隧道先行洞开挖所揭露的围岩变形模量E、泊松比μ进行了位移反演,及时掌握先行洞开挖后围岩物理力学参数,从而达到优化设计并指导后行洞施工的目的,以实现隧道的信息化施工与设计。     

红砂岩单轴压缩蠕变试验及模型研究

为了研究红砂岩蠕变特性,对红砂岩进行了单轴压缩蠕变试验。以试验结果为基础,建立了非线性黏弹塑性蠕变模型,并基于BFGS非线性优化算法对该模型参数进行了识别。结果表明,红砂岩具有明显的蠕变特征,建立的模型可以同时表征岩石瞬时加载应变、衰减蠕变、稳态蠕变以及加速蠕变等蠕变特征。最后,将非线性黏弹塑性蠕变模型进行了大型有限差分法软件FLAC3D的二次开发,并对红砂岩单轴蠕变数值模拟试验,同时将数值模拟蠕变曲线与试验蠕变曲线进行了比较分析,验证了非线性黏弹塑性蠕变模型的实用性。     

基于有限元法的矿用隔爆型圆筒形外壳设计

采用弹塑性力学理论对外壳进行初始化设计,运用Solidworks软件将得到的设计参数对圆筒形外壳建模,再利用COSMOSworks软件对壳体和壳盖静载工况的应力进行有限元分析,根据分析结果整体降重后,再次计算实体应力,以检测改后的结果能否达到强度、刚度要求。     

矿用自卸车ROPS结构研究

本文以某矿用自卸车为研究对象,类比设计一种集成式ROPS结构,并基于ANSYS软件依据标准ISO 3471-2008进行加载分析。通过对加载过程中ROPS结构变形量的分析,判断ROPS结构是否能满足标准规定的性能要求。分析结果显示,在侧向、垂直、纵向加载过程中,ROPS部件没有任何部分侵入DLV界面,表明在车辆发生倾翻事故时该ROPS结构可以对驾驶员起到有效保护作用。     

基于稳定度的装载机稳定性评价

以稳定度为基础对装载机的稳定性进行了评价;分析了基于稳定比评价方法的不足;对装载机不转向时在坡道上的纵向稳定度、装载机不转向时在坡道上的横向稳定度、装载机转向时在坡道上纵向的稳定度和铰接装载机转向时的横向稳定度等做了详细的分析和计算;为装载机稳定性的研究和计算提出了一种新的思路。     

蟹爪式装载机的总体设计

对蟹爪式装载机在煤矿中的应用做了简单介绍,分析了煤矿用装载机在设计之前应考虑的主要因素。探讨了蟹爪式装载机总体性能参数和总体尺寸参数的计算方法,为煤矿用蟹爪式装载机的设计提供参考。     

卡特彼勤公司地下装载机主要技术参数与结构特点

卡特彼勒公司是世界上著名的露天工程机械和矿山设备制造商,从1983年就开 始生产地下装载机,并计划在2005年占世界地下装载机的主导地位。本文介绍该公 司生产的地下装载机主要技术参数与结构特点。     

矿用自卸车ROPS的有限元分析和结构改进

以某168 t矿用自卸车为例,结合承载能力和自身轻量化的要求,建立翻车保护结构的有限元模型,根据国际标准的要求进行仿真,并提出了2个改进模型的方案,使分析结果达到翻车保护结构在满足性能要求的前提下轻量化。     

国外地下装载机的最新发展

根据国外地下装载机的最新信息,简略地介绍它的新变化,新品种、新技术和新发展、为发展我国地下装载机与选用国外新机型提供参考。     

Design of automated loading buckets

Conclusions The study has shown the possibility of designing automated loading elements which can make the operation of machines easier, improve the dynamic conditions of work, and raise the efficiency of remote-controlled loaders. The classification of loaders according to the principle of suspension of the bucket and the corresponding schemes of placement of sensors encompasses all underground loading, unloading, and transportation machines, surface frontal loaders, and power shovels with loading units. The horizontal or tangential components of the forces of resistance to bucket advance in the rock pile or the moments from one of these forces relative to the suspension axis of the loading equipment on the gantry can be used as the main control signal; the moment from the resultant force relative to the suspension axis can also be used. Functional flowcharts of systems with automatic scooping of rock mass are suggested for loaders, transporters, frontal loaders, rock loading machines, and power shovels with bucket-type loading equipment. The choice of the placement of sensors, the signals, and the functional flowcharts of the control systems is based on experimental tests of mass-produced front-end loaders TO-1 (T-157) and TO-7 (D-574) manufactured by Berdyansk DORMASh Factory, frontal TO-6 (D-561) made by Orlov Loader Factory, rock-loading mine machine MPR-6, and loader-transporter BD-8M equipped with experimental automatic control systems. The machines have been tested in industrial trials with loading of non-ore materials in quarries, granular and lumpy material at railroad stations, and with the loading of rock masses of different particle sizes in underground mines and quarries. The results of the study are being used in the design of Soviet automated loading and transporting machines at the Institute of Mining Machine Desing and Development; they can provide a basis for developing a family of front-end loaders and power shovels with a bucket-type loading unit. Institute of Mining, Siberian Branch of the Academy of Sciences of the USSR, Novosibirsk. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 4, pp. 79–86, July–August, 1986.     

CY922D型柴油地下铲运机结构特点分析

目前，在国产柴油铲运机中推广台数最多的是ＣＹ９２２Ｄ型铲运机。本文阐述了该铲运机在矿山的使用情况、结构特点及与同类铲运机的比较所显示的优越性。     

Stress distribution in attachments of disc cutters in heading drivage

The authors substantiate new engineering designs for selective heading machines and cutter–loaders fitted with screw–type cutters. It is proposed to use biconical and conical disc tools and their attachment units to polygonal prisms to equip both bits of heading machines and screw cutters of cutter–loaders to cut structurally heterogeneous rock mass. It is recommended to practice reverse–mode operation of universal radial–type drill bits fitted with disk tools mounted on triangular prisms with a view to widen the front of loading to be imposed on sidewalls. The presented data on modeling stress state of disk tools and variants of their attachments to polygonal prisms show the mechanisms of loading of related parts in the course of rock cutting.     

Application of compound Poisson process for modelling of ore flow in a belt conveyor system with cyclic loading

Abstract

This paper deals with the analysis of the random process of cyclic loading of a mining belt conveyor with portions of ore discharged by loaders or trucks. Such transfer of transported ore from a cyclic to a continuous transport is typical for the specific mining operations implemented in the underground copper ore mines with room and pillar mining. The conveyors in such systems are usually significantly oversized in order to match the peak loads of cumulated discharges of ore hauled from mining fields by loaders. Therefore, the actual loadings that occur in the mining transportation systems need to be analysed to provide the data for more accurate design and control of belt conveyors. The large data-set of actual loadings of the belt conveyors has been used for the stochastic modelling of the analysed process. The compound Poisson process has been proposed as mathematical tool to analyse/describe properties of ore flow. The discussion of the chosen distribution functions and results of the fitted model simulations compared with the examined measurement data are presented. In this paper, the case of a belt conveyor loaded only by a single feeding point where loaders are randomly discharged have been analysed. More complex cases (several loading points, mixed ore supply from cyclic and continuous ore mass flow from preceding conveyors or ore bunkers) are under investigation and will be presented in the future.