低压废热锅炉密封工装板破裂失效事故技术分析及改进措施

本文分析导致低压废热锅炉密封工装板破裂失效事故的直接原因是工装结构强度不足和工装制造质量存在严重问题,间接原因是企业工艺流程管控不严、不重视产品辅助工装的制造质量和安全管理不到位。针对存在的问题提出了几个改进措施,为预防类似事故的发生提供借鉴。     

风电叶片在后打孔模具上实现预埋螺栓套成型的工装结构研究

主要阐述了风力发电机叶片在后打孔模具上实现预埋螺栓套成型工艺的工装结构形式可行性研究.通过项目的研究与实施,创新完成后打孔模具制作预埋叶片的定位工装实现方案,解决了预埋定位工装在后打孔模具上连接及螺栓套后定位精度的技术难题,保证了预埋工艺叶片在后打孔模具上的新开发试制,从而实现了现有后打孔模具资源闲置与重新制作预埋模具增加生产成本的矛盾的有效整合.     

锥形弹簧粘接试验自动检测工装的研制

从试验工装的结构与功能优化、辅助上下料机构优化和试验结果自动判定优化等方面着手,针对锥形弹簧类产品的粘接试验应用了新型自动调节工装。结果表明,将六爪卡盘式可伸缩结构应用于常规检测工装,解决了原工装检测效率低、产品碰伤风险高、劳动强度大、换型时间长和试验结果依赖人工判定等技术难题;同时,还利于规避因工装型号种类多带来的管理难度大、开发制作周期长和综合成本高等管理问题;实现了检验手段的创新,显著提升了检测效率。     

T型复合材料长桁承载能力设计研究

应用商业有限元软件ABAQUS中的内聚单元,对复合材料T型长桁的缘条／蒙皮界面失效进行了分析,计算结果与试验数据吻合良好。基于有限元结果,提取了缘条／蒙皮界面内力,研究结构的失效机理。以缘条和蒙皮厚度为参数进行参数化建模,研究缘条／蒙皮刚度比对界面失效乃至承载能力的影响。最后对缘条／蒙皮刚度比提出了设计建议。     

复合材料机身Z型隔框变形控制研究

采用单向带预浸料在Z型隔框成型工装上完成零件的铺贴及固化,在零件切边以后采用三坐标测量机完成零件的型面测量,将测量数据与零件理论型面进行了分析对比。分析了零件缘条与腹板之间的回弹、零件在半径方向以及在腹板方向上的变形情况,并根据工程对零件型面的要求,对隔框成型工装进行了型面补偿,得到了工装设计的零件工艺数模。采用完成型面补偿以后的工装制造了全尺寸隔框零件,采用三坐标测量机对零件型面进行了测量,验证了工装型面补偿的有效性,零件型面轮廓度控制在±0.375 mm以内,隔框在与角片及蒙皮进行装配的过程中,很好地满足了装配公差的要求。     

多面体异型蜂窝夹层结构板整体成型技术研究

本文以某卫星收纳箱产品研制任务为背景,阐述了多面体异型蜂窝夹层结构板整体成型技术。首先介绍了产品结构特点,其次分别从工艺方案、成型工装设计与仿真分析、复合装配等方面进行了探究,最后从技术和质量方面进行了总结。结果表明,该整体成型技术方案可行,通过成型工装优化设计、蜂窝夹层结构外蒙皮整体成型与内蒙皮分瓣成型相结合的复合装配等成型技术,解决了收纳箱结构形面精度及拐角位置胶接质量难以控制的难点,制造的收纳箱产品内部质量和尺寸精度均满足设计指标要求。     

民用客机大型复合材料蜂窝夹芯尾缘胶接技术研究

本论文以民用大型复合材料尾缘为研究对象,创新研制双曲面蜂窝数控切削及检测一体化工装,确保加工与检测基准的一致性,提高了蜂窝检测的可靠性;研制的蜂窝芯实现表面平整度在±1.25mm内;蜂窝芯分段处阶差≤0.15mm;蜂窝零件装配型面精度±0.15mm。开展次级零件及胶接组件复合材料工装热分布分析,合理选取固化参数;首次采用楔形活块工装设计,对窄腔薄壁复合材料蒙皮变形进行补偿,实现窄腔薄壁蒙皮高质量成型。成型蒙皮的外形尺寸轮廓度为0.2,薄壁窄腔蒙皮窄腔处U型位置厚度公差≤±2%;成型后薄壁窄腔蒙皮孔隙率≤1%;民用客机大型复合材料尾缘的成功研制,对于推进复合材料胶接技术水平,推动复杂大型复合材料整体构件的应用意义重大。     

浅谈汽车涂装辅助工装的多车型通用设计与应用

从同线体车型共用、多车型工艺可行性、操作使用性等方面阐述了涂装工装辅具的设计理念,结合某汽车公司涂装辅助工装的实际应用,简单介绍了涂装工装辅具的开发设计过程和应用案例。     

汽车白车身窗框电泳流痕改善

阐明了车门窗框电泳流痕产生的原因,分别从钣金结构的设计、钣金加工精度的控制及工装导入辅助等方面进行对策验证,为车门窗框电泳流痕的消除提供了明确的思路。     

载重轮胎垫带防爆片安装工装的设计

介绍载重轮胎垫带防爆片安装工装结构和实施方式。该安装工装主要由支座、支座架、支承轴、压盖、压盖架和销轴组成,采用支座限位防爆片,支承轴将垫带引到防爆片子口上,压合机构实现系统压合功能,压盖辅助垫带压缩,保证垫带准确镶嵌于防爆片内子口上。该安装工装移动、携带方便,操作不受场地、能源介质限制,运行成本低。     

复合材料与无人飞机

本文论述了无人机对复合材料的需求，给出了复合材料在无人机上应用的概况以及无人机复合材料技术发展研究的要点。     

低速小型无人机中的复合材料结构及分析

复合材料结构在小型无人驾驶飞机中占据着主导地位。随着无人机的发展，以复合材料为主体的无人机结构型式已有多种。本文就小型无人机复合材料结构的特点进行分析，给出了一些典型的复合材料飞机结构型式，并进行了结构布局选择分析和结构设计分析。     

Experimental and numerical analysis of flow behavior in the FASTRAC liquid composite manufacturing process

The success of resin infusion during liquid composite processing depends on several factors; including the complete impregnation of the dry performs, the processing conditions, and the tooling used during processing. New process developments based on the Fast Remotely Actuated Channels (FASTRAC) process aid the infusion with the creation of preferential resin flow paths using a non-contact tooling. Experiments to understand and study the infusion behavior with the presence of the FASTRAC non-contacting tooling have been performed, and compared with vacuum-assisted processes without such tooling. Experimental studies indicate that the infusion time with FASTRAC channel configurations is significantly less despite the additional volume regions to be infused during processing. The use of a non-contacting interchangeable tool, the improved infusion behavior, and the significant reduction in the infusion time provide significant advantages for processing advanced composite systems, including the potential to use high viscosity resin systems, and process automation. The process simulation models of the experimental configurations based on the thin shell model configurations have been compared with experimental observations. Studies indicate that the process simulation models and approaches employed clearly emulate the infusion behavior seen when the channels are present, validating the modeling strategies employed. Similar simulation approaches will thus be effective to study and understand various FASTRAC tooling configurations while processing complex composite structures. Polym. Compos. 25:384–396, 2004. © 2004 Society of Plastics Engineers.     

Effective properties of particle reinforced polymeric mould material towards reducing cooling time in soft tooling process

Cooling time in soft tooling process using conventional mold materials is normally high. Although increase of effective thermal conductivity of mold material by inclusion of high thermally conductive fillers reduces the cooling time, it affects other properties (namely, stiffness of mold box and flow ability of melt mold material), which play important roles in soft tooling process. Therefore, to apply composite polymer in soft tooling process as mold material simultaneous studies of these properties are important. In this work, extensive experimental studies are made on the effective thermal conductivity, modulus of elasticity and viscosity of composite polymeric mold materials namely Polyurethane and RTV (Room Temperature Vulcanizing)‐2 silicone rubber, with aluminum and graphite particle reinforcements. To find suitable models of the effective properties of composite mold materials, which are required to decide the optimum amount of filler content before actual application, attempts are made to fit the experimental results using various models reported in the literature. Finally, different aspects in reducing cooling time in soft tooling process and further activities are reported. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

基于ANSYS/FE-SAFE的无人机复合材料机翼疲劳分析

计算了某无人机复合材料机翼的静强度,使用局部应力-应变疲劳分析理论,基于正弦载荷激励,按照累积损伤理论和雨流计数法则,应用ANSYS/FE-SAFE软件,分析了此无人机机翼的疲劳寿命,为复合材料机翼疲劳分析提供了新的分析途径.     

基于ANSYS/FE SAFE的无人机复合材料机翼疲劳分析

 计算了某无人机复合材料机翼的静强度,使用局部应力 应变疲劳分析理论,基于正弦载荷激励,按照累积损伤理论和雨流计数法则,应用ANSYS/FE SAFE软件,分析了此无人机机翼的疲劳寿命,为复合材料机翼疲劳分析提供了新的分析途径。     

Spark plasma sintering of structure-tailored ultrahigh-temperature components: First step to complex net shaping

The net-shaping capability in spark plasma sintering (SPS) of ultrahigh-temperature ceramics has been explored in this study. The annular or ring-like shape is considered here as the first step to a more complex geometry compared to a solid cylinder or disk. ZrC powders have been SPS processed in specially designed graphite tooling to achieve the annular shape geometry. Experimental runs have been carried out to determine the optimal processing parameters for producing highly dense ZrC specimens in this geometry. Finite-element modeling framework has been constructed to determine the internal stress evolution, as well as densification, during the SPS of the annular-shaped ZrC. The formulated processing schemes for ZrC have been adapted to process SiC/ZrB₂ composite powder with the purpose of making tooling components for SPS applications. The applicability of the obtained composite SPS tooling has been evaluated at high temperature and high pressure associated with SPS regimes.     

小型无人机复合材料机身壁板与梁整体制造工艺

通过介绍无人机复合材料机身的结构特点、传统制造工艺方法以及工艺所存在的诸多问题,介绍了一种中小型无人机机身复合材料整体压力垫的制造工艺,以及复合材料蜂窝夹芯板件与梁整体共固化的工艺过程,可以用于典型的梁框蜂窝夹芯结构的整体制造。结果表明,通过与传统工艺对比,可以降低无人机的生产成本,提高复合材料制件的表面质量,缩短零部件生产周期。     

Low cost tool builds ISS parts

A LOW cost composite tooling system developed by Boeing and RenShape Solutions is being used to make parts for the International Space Station.This is a short news story only. Visit www.reinforcedplastics.com for the latest plastics industry news.     

几何扭转的无人机机翼复合材料结构设计

具有几何扭转的无人机机翼其机翼外形是复杂的扭曲面,给制造特别是装配协调带来难度。文中介绍了针对几何扭转的无人机机翼的复合材料结构设计,采用巧妙的工艺设计思想,利用复合材料共固化翼面结构将复杂扭曲面的协调装配简化,从而解决了几何扭转的无人机机翼的低成本制造问题。针对某型无人机所设计的几何扭转机翼已经取得成功应用。