微型液压吊车四构件系统参数的算法设计

研究了一种微型液压吊车四构件系统参数自动化高精度的求解方法.为解决微型液压吊车四构件系统参数传统求解方法的效率低、精度差问题,采用三角函数结合运动学推导得到各参数的数学表示,提高了参数求解精度.采用微分思想对四构件系统的运动过程进行了分析和算法设计,解决了传统方法难于确定液压缸活塞杆最大受力位置的问题.全部所需参数采用程序求解,使计算迅速而准确.     

基于Virtools的齿轮泵虚拟装配训练系统

齿轮泵的装配训练是液压系统维修培训中重要的一部分.为了提高学校及培训机构的训练质量,使工人能够快速掌握齿轮泵的装配,设计了基于Virtools的齿轮泵虚拟装配训练系统.描述了基于Virtools的齿轮泵虚拟装配训练系统的总体设计思想,通过CATIA平台建立了齿轮泵产品元件的三维实体模型,在此基础上利用Virtools平台设计了交互式的齿轮泵虚拟装配训练系统.该系统为使用者提供了界面友好、交互性好、操作便利的训练环境,能够满足学校及培训机构的训练需求.     

陆地钻机钻杆自动起升系统的设计与优化

由于国内陆地钻机利用钻台气动绞车或吊车实现钻杆上下钻台时不稳定、效率低,本文设计了一套用于陆地钻机的钻杆自动起升系统,该系统可以实现钻杆在井场排放架和钻台之间自动传送,极大地缩短了钻井周期,提高了钻井效率.并利用ANSYS有限元软件对该系统的关键部件进行了有限元分析和结构优化,优化后的系统具有足够的强度、刚度和稳定性,满足长期使用的需要.     

SIEMENS系统数控机床维修技巧

介绍数控机床常见故障的识别方法,针对生产实际中常用的SIEMENS系统数控机床,提出常见故障源的维修技巧和维修提示.实践证明,使用这些方法大大提高了维修效率.     

ZG55 Ⅱ吊车车轮断裂失效分析

针对断裂的吊车车轮进行了失效分析,采用宏微观形貌、化学成分、金相显微组织、SEM微观断口形貌、EDS微区成分分析等手段,分析了吊车车轮断裂的原因.结果表明,吊车车轮断裂为疲劳断裂.表面脱碳、冶金缺陷以及热处理缺陷是导致吊车车轮疲劳断裂的三个主要原因.     

基于UML的工程机械维修管理信息系统分析与建模

工程机械维修业务涉及的部门科室多,业务流程复杂,采用传统的系统构建方法不利于模型与程序的结合.在对某工程机械修理厂维修业务流程进行优化的基础上,运用统一建模语言(UML),对工程机械维修管理信息系统建立了一系列UML模型,系统地描述了工程机械维修管理信息系统的功能需求、静态结构和动态行为,从而使开发者更好地熟悉系统的业务流程,提高了系统开发的效率.     

吊车梁焊接工艺优化及控制变形措施

吊车梁是一个很重要的承重钢结构 ,对焊接质量要求比较高 ;另外 ,由于其结构尺寸 (长度和高度 )都很大 (例如 ,淮北二电厂吊车梁长度达 12 .3ｍ ,高度为 1.8ｍ) ,很容易产生扭曲等焊接变形 ,这种焊接变形一旦产生 ,不但矫正起来相当困难 ,而且造成人力和物力的浪费。本文针对这一客观事实 ,通过实践、分析和归纳总结 ,形成了一套比较完整的吊车梁焊接工艺和控制焊接变形措施 ,以优化吊车梁焊接质量 ,提高焊接生产效率 ,降低焊接生产成本。1　技术要求吊车梁的上翼缘板与腹板的Ｔ形焊缝要求做10 0 %的无损探伤 (超声波检验 ) ,焊接接头质量要…     

后桥气冲造型线上位机监控系统软件的开发与应用

本文介绍了监控系统软件的设计思想、开发处理过程及其特点。该系统集实时动态监控、故障自诊断处理、故障分析统计、生产过程管理、信息统计报表等功能于一体，解决了复杂设备的生产管理、快速诊断以及指导维修等问题。     

FRKS-Ⅱ型飞机防滑刹车测试系统的设计

介绍了FRKS-Ⅱ型飞机防滑刹车测试系统的设计,该测试系统是一种以计算机为核心,根据用户需求并借鉴国内外在计算机硬件和软件、液压比例控制、计算机辅助测试方面的新技术和新产品而设计的.软件设计注重测试项目的工况状态建立、测试参数采集、测试数据处理,以及对泵站压力、油液温度进行闭环控制,对操纵力等关键参数进行实时监视并提供系统的维修、清洗、标定、校正等内容.该测试系统是典型的机-电-液一体化设备,具备一定的升级扩充功能.     

铜合金铸造工艺CAD系统关键技术研究

基于国标的铜合金专用铸造工艺CAD系统能有效地提高工艺设计的效率和准确性.介绍了开发铜合金铸造工艺CAD系统的部分关键技术--初始化绘图环境、图形实时绘制、菜单开发和基于MFC的ODBC与Access的数据交换等,并阐述其应用方法.     

Three-Dimensional Growth of Coherent Ferrite in Austenite: A Molecular Dynamics Study

Coherent second phase often exhibits anisotropic morphology with specifi c orientations with respect to both the second and the matrix phases. As a key feature of microstructure, the morphology of the coherent particles is essential for understanding the second-phase strengthening eff ect in various industrial alloys. This letter reports anisotropic growth of coherent ferrite from austenite matrix in pure iron based on molecular dynamics simulation. We found that the ferrite grain tends to grow into an elongated plate-like shape, independent of its initial confi guration. The fi nal shape of the ferrite is closely related to the misfi t between the two phases, with the longest direction and the broad facet of the plate being, respectively, consistent with the best matching direction and the best matching plane calculated via the Burgers vector content(BVC) method. The strain energy calculation in the framework of Eshelby's inclusion theory verifi es that the simulated orientation of the coherent ferrite is energetically favorable. It is anticipated that the BVC method will be applicable in analysis of anisotropic growth and morphology of coherent second phase in other phase transformation systems.     

Effect of Short-Time Aging on the Pitting Corrosion Behavior of a Novel Lean Duplex Stainless Steel 2002

The effect of short-time aging in the temperature range between 400 and 1000 °C on the pitting corrosion behavior and mechanical property of a novel lean duplex stainless steel(LDSS) 2002 was investigated through the potentiostatic critical pitting temperature(CPT) tests and the Charpy impact tests. Both the pitting corrosion resistance and the toughness of aged specimens degraded due to the precipitation of detrimental secondary phases and the most significant reduction of CPT and impact energy emerged at 650 °C concurrently. The CPT of LDSS 2002 specimen aged at 650 °C decreased by 28 °C, and the impact energy dropped from 69 to 29 J/cm~2 compared with the solution-annealed sample. Transmission electron microscopy characterization showed that the main precipitates in LDSS 2002 were Cr_2N and M_(23)C_6 along the ferrite–austenite grain boundaries.     

INTRODUCTION TO PATENTS

The invention provides a method of making a mold which can reduce SOx generation rate while preventing decrease in hardening rate in the case of using sulfuric acid for a hardener composition. The method has a mixture step in which fire-resistant particles, a hardener composition and a binder composition are mixed to obtain a composition for a mold. The hardener composition contains sulfuric acid. In the mixture step, sodium carbonate is added. A molar ratio of the sulfuric acid to the sodium carbonate is 0.5 or more and 4.0 or less.     

China Foundry Week 2014

China Foundry Week, hosted by the Foundry Institution of Chinese Mechanical Engineering Society （FICMES） each year, is a large academic event in China. It is one of the ten high-impact activities sponsored by the Chinese Mechanical Engineering Society.     

17th Conference of Hydrodynamic and Electromechanical Control Engineering Call for papers

正1.Contents In order to promote the academic exchanges and technical communication of the research in the field of fluid power transmission and control,fluid control engineering specialized committee of the Chinese Society of Theoretical and Applied Mechanics will hold the 17th Conference of Hydrodynamic and Electromechanical Control Engineering on July 27-29,2014 in Tibet,Lhasa city.     

Information for Contributors

正The Transactions of Nonferrous Metals Society of China,founded in 1991 and sponsored by The Nonferrous Metals Society of China,is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology,including mineral processing,extraction metallurgy,metallic materials and heat treatments,metal working,physical metallurgy,powder metallurgy,with the emphasis     

Preface

<正>We are pleased to present this Special Issue of Transactions of Nonferrous Metals Society of China containing selected papers from the First Asian Conference on Aluminum Alloys(ACAA-2013),held in Beijing,China,13–17 October 2013.This conference has been initiated,with approval of     

Information for Contributors

The Transactions of Nonferrous Metals Society of China, founded in 1991 and sponsored by The Nonferrous Metals Society of China, is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology, including mineral processing, extraction metallurgy, metallic materials and heat treatments, metal working, physical metallurgy, powder metallurgy, with the emphasis on fundamental science. It is the unique preeminent publication in English for scientists, engineers, under/post-graduates on the field of nonferrous metals industry. This journal is covered by many famous abstract/index systems and databases such as SCI Expanded, Ei Compendex Plus, 1NSPEC, CA, METADEX, AJ and JICST.     

FORMULAS OF TENSION OF CONTINUOUS ROLLING PROCESS

The development of computer controlled continuous rolling process calls for a mathematical expression that can express the inequality condition of "constant flow". Tension is the link of the continuous rolling process. From the condition of dynamic equilibrium, a differential equation of tension is given out. On the basis of the physical rules established from the industrial practice and experimental studies, the law of volume constancy, the linear relation of forward slip and tension, the state equation of continuous rolling, the formula of dynamic tension, and the formula of static tension have been obtained. These formulae reflect the functional relations between tensions, thickness, roll velocity, and time in the continuous rolling process. It is implied that the continuous rolling process is a gradually steady, controllable, and measurable dynamic system. An assumption of predicting the thickness of a steel plate using these tension formulae is also put forward.     

Bulletin of the Awards in 2013

<正>Five reviewers and 9 published articles are selected as the Excellent Rewewerand Excellent Article in 2013 respectively.Excellent Reviewers:Prof.Z ongyi Ma(Institute of Metal Research,CAS,C hina);Prof.Y ongbo Xu(Institute of Metal Research,CAS,C hina);Prof.Guangping Zhang(Institute of Metal Research,C AS,C hina);Prof.Z hendui Cui(Tianjin University,China);