某车型尾门装饰条变形分析

尾门装饰条受热胀冷缩影响,容易变形或断裂;针对某车型尾门装饰条变形的现状,利用理论和实际相结合以及CAE分析手段分析在不同工况下尾门装饰条的变化量,综合查找导致装饰条变形原因,并根据具体原因制定整改对策,根据装饰条热胀冷缩的原理,对策主要包含两个方面,一是变形量得到释放,二是改善尾门装饰条本身的变形量;这两个方面的实施改善了尾门装饰条变形的问题。     

贮罐侧入式搅拌轴封失效分析

从工程实际出发，对贮制度侧入式搅拌轴封因制造误差和维修不当等因素造成的失效进行了分析和治理，取得了较好效果。     

轿车前轮毂轴承早期失效与配合精度的相关性分析

本文就桑塔纳轿车前轮毂轴承一度出现的早期失效现象进行了分析。针对与前轮毂轴承内外套圈配合的轴颈及轴承座孔的配合过盈量进行理论分析 ,经过分级试验 ,由振动及温度监测轴承运转性能 ,合理地确定了圆柱度精度的级别。附图 1幅 ,表 1个 ,参考文献 1 1篇。     

立体车库钢结构失效模式分析简化模拟及失效准则

基本结构系统可靠性失效模式的概念，探讨立体停车库钢结构系统简化模拟方法，提出结构系统失效准则的合理性原则，即工程结构系统失效不能笼统地定义为结构系统蜕变为机构，而应定义为结构系统中某些关键元件失效后，整个结构系统失效去继续承载能力或完成规定功能的能力，本原则不仅适用于立体停车库钢结构系统，而且对于其它结构系统也具有理论与实际指导意义。     

石化企业承压设备安全阀失效模式及失效原因

通过对石化企业典型装置安全阀运行状况和校验时状况的调查,以及校验时安全阀开启压力的试验研究,得出石化企业安全阀失效模式和失效原因。     

阀门失效模式的分析及解决方法

针对阀门失效所导致的安全事故及不利影响,在阀门故障类型与故障分析的基础上,简述阀门不同的失效模式及失效原因.从材料、设计、试验与制造的角度提出解决方案,最后对阀门可靠性研究及其发展趋势进行展望.     

浅谈变速箱侧推式分离机构故障及预防措施

针对变速箱离合器分离机构故障进行原因分析,对其典型的失效模式进行系统性分析并制定相应的措施,进一步提高对变速箱侧推式分离机构的认识,从而将其运用到日常设计工作中。     

浅析电磁继电器常见的失效原因及失效机理

电磁继电器因其结构简单、工作可靠在汽车电子控制系统中有着广泛的应用,电磁继电器的失效将影响整个汽车电子系统的可靠运行。本论文主要介绍了电磁继电器的基本结构、工作原理和特性,并对电磁继电器在使用工作过程中常见的失效模式及其失效原因进行了系统分析,旨在为处理电磁继电器的故障分析与生产过程工艺管控提供思路与理论支持,对于电磁继电器的应用、常见故障排查与分析,以及生产质量管控、提升继电器可靠性具有一定的指导意义。     

用失效机制模型对大型复杂产品进行失效模式影响分析

为了有效地降低新产品研发的风险,提高产品可靠性,必须进行失效模式分析,但大型复杂产品的系统复杂性,给全面分析失效模式的影响和原因带来困难。文章从产品的用户需求出发,对产品的功能进行分析,并从产品结构中找出失效的原因,建立了失效机制模型。通过对微电子装备的研发进行分析,该模型能明显地克服产品研发中的风险。     

汽车前纵梁碰撞特性仿真研究

汽车的碰撞安全性是影响汽车被动安全性的主要方面,汽车部件的碰撞仿真是确保车辆具有良好碰撞性能的一种重要的现代设计方法和手段,汽车前纵梁作为一种典型的薄壁梁结构件,是保证汽车具有较好正面碰撞性能的重要部件.笔者利用非线性有限元软件ANSYS/LS-DYNA对某SUV车型前纵梁进行计算机碰撞仿真分析研究,比较了改进前后前纵梁的碰撞吸能特性.研究表明经改进设计后,前纵梁的碰撞特性得到加强,研究方法和结果对汽车前纵梁设计具有实际应用价值和直接指导意义.     

新型轨道运料车转向架构架结构分析

在参考国内一些列车转向架结构的基础上,设计出一款新型低速轨道运料车转向架.根据国际铁路联盟规程UIC 615 4—2003标准进行构架载荷分析与相应工况的载荷计算,并利用ANSYS Workbench有限元软件对构架正常运行和超常运行两种工况下的应力以及变形进行分析.计算结果表明该转向架构架结构满足静强度要求.     

基于制造成本的某纵梁冲压工艺方案研究

为解决纵梁类零件按照传统拉延工艺方案制备时材料利用率低、制造成本高的问题,以某汽车纵梁为研究对象,根据其形状特征制定了复合成形的工艺方案,并利用AutoForm软件对纵梁进行成形性模拟。结果表明,采用复合成形的工艺方案能够有效地控制纵梁类零件回弹的缺陷,提高了材料利用率,降低了制造成本。该工艺方案对纵梁类零件的实际生产有重要的指导作用。     

基于虚拟试验场技术的汽车侧面碰撞仿真分析

以显式动态有限元理论为基础,基于虚拟试验场(VPG)技术,对汽车侧面碰撞进行计算机仿真研究.在VPG环境下,对整车CAD模型划分了单元网格,定义了单元类型和材料参数,创建了焊点、接触和约束.参照ECE R95安全法规,加载移动壁障车模型,并设置碰撞初始条件.调用显示动态有限元软件LS-DYNA对仿真模型进行计算求解,得到汽车碰撞过程中应力分布和车身变形云图,以及碰撞能量和加速度曲线.通过仿真可预测出汽车碰撞的安全性能,从而为汽车质量的评价提供了依据.     

阀门故障分析及其分类

探讨了根据阀门故障的发生特点、影响程度和起因对阀门故障分类的方法。按照机械产品故障模式特点对阀门常见故障模式进行分类，是一种切实可行的综合分类方法。应用该分类法，对特定类型阀门——安全阀的主要故障现象进行了分析和分类。     

Analysis of unavoidable geometric errors in the side wall of end-milled parts for corner surface

The location and the size of a geometrically defected region in the side wall of a corner, which is generated during the flat end-milling process, are investigated through experiments and geometrical analysis. A corner with inner and outer surfaces is assumed to be made up of one arc-surface patch and two flat-surface patches. Based on the previous findings that the change of material removal per tooth affects the geometry of the end-milled side wall, it is expected that the geometrically defected regions are located around the corner when the tool is approaching and leaving the arc surface. In this respect, analytic models are proposed to predict the location and the size of a geometrically defected region, which are then validated via comparison with the experimental results. This paper was recommended for publication in revised form by Associate Editor Dae-Eun Kim Kun Sang Lee received his B. S. degree in Mechanical Engineering from Seoul National University, Korea, in 1982. He then received his Dipl.-Ing. and Dr.-Ing. degrees from Technical University of Berlin, Germany, in 1991 and 1993, respectively. Dr. Lee is currently a Professor at the School of Mechanical and Automotive Engineering at Kookmin University in Seoul, Korea. He serves as a Staff of the Korea Engineering Education Research Center. His research interests include precision machining, high energy beam material processing, and creative design methodology. Kang Kim received his B. S. and M. S. degrees in Mechanical Design and Production Engineering from Seoul National University, Korea, in 1982 and 1984, respectively. He then received his Ph.D. degree from Purdue University, USA, in 1992. Dr. Kim is currently a Professor at the School of Mechanical and Automotive Engineering at Kookmin University in Seoul, Korea. His research interests include material removal processes, and concurrent engineering.     

On-line and off-line wheel/rail contact algorithm in the analysis of multibody railroad vehicle systems

An on-line and off-line hybrid contact algorithm for modeling wheel/rail contact problems is developed based on the elastic contact formulation. In the hybrid algorithm developed in this investigation, the off-line tabular search is used for predicting the location of tread contact points, while the on-line iterative search is used for predicting flange contact points. By so doing, a computationally efficient procedure is achieved while keeping accurate predictions of contact points for severe contact scenarios such as sharp curve and turnout negotiations. The use of the proposed hybrid algorithm can eliminate the time-consuming on-line iterative search for the second points of contact. Since the location of the second point of contact is pre-computed by the contact geometry analysis, the occurrence of two-point contact can be predicted by using the look-up table at the one-point contact configuration. A flange climb simulation demonstrates that the proposed hybrid contact search algorithm can be effectively used for modeling wheel/rail contacts in the analysis of general multibody railroad vehicle systems. This paper was presented at the 4th Asian Conference on Multibody Dynamics(ACMD2008), Jeju, Korea, August 20–23, 2008. Hiroyuki Sugiyama received his Ph.D. from the University of Illinois at Chicago in 2005. Dr. Sugiyama is currently an Assistant Professor at Tokyo University of Science, Tokyo, Japan. His research interests include the development of computer formulations for contact problems in vehicle systems and the large deformation problems of constrained multibody systems. Kohei Araki received his BS degree in Mechanical Engineering from Osaka City University in 2006. Mr. Araki is currently a Master’s student at Osaka City University, Osaka, Japan. His research interest is in the modeling of wheel/contact problems in railroad vehicle dynamics. Yoshihiro Suda received his Doctoral degree from the University of Tokyo in 1987. Dr. Suda is currently a Professor at the University of Tokyo, Tokyo, Japan. His research interests are in the dynamics of railroad vehicles and automobiles, in-telligent transportation systems (ITS) and personal mobility vehicles. He is currently serving as an Associate Editor of the IMechE Journal of Multi-Body Dynamics.     

柴油机高压共轨系统ECU的设计

本文首先介绍了最具代表性的Bosch公司的高压共轨系统,据此进行了电控系统的软硬件设计和控制策略设计,通过试验,达到了预期的设计效果。     

大型零件装配搬运的智能轨道系统驱动控制

智能辅助作业设备(IAD)是新一代人机工程学与智能控制技术相结合的产物,智能轨道系统是IAD的关键部分之一.根据搬运大型零件时智能轨道系统的功能,设计了H型钢与智能移动单元构成的模块化导轨结构,其具有主动、欠驱动力和被动工作模式.研制了智能轨道系统实验样机,进行了半物理仿真实验研究.研究结果表明:该轨道系统能够跟踪给定的速度指令和位置指令,并且跟踪性能满足设计要求,可以应用于大型零件的装配搬运等作业场合,并为IAD产品的推广和实用化提供了参考价值.     

岸桥小车轨道压板螺栓松动及开焊的原因分析

重点介绍岸桥作业中由于小车频繁过轨振动引起的轨道压板螺栓松动或压板处开焊的现象。通过螺栓松动的原因分析及压板焊缝开裂的研究,找出修复解决办法,避免此种情况的发生。