凸轮进给式双管平头倒棱机

研制的凸轮进给式双管平头倒棱机可自动完成上料→夹紧→平头倒棱→松开→退料动作循环，同步准确，可靠性高，平头倒棱质量好。介绍了该装置的工作原理、工作程序、技术性能、设备组成以及刀具和夹具的特点。     

计算机网络安全漏洞及解决方案初探

随着Computer Science和IT技术的迅速发展,计算机及网络技术已经逐步渗透进入人们的日常生活,但是目前由于网络具有的开放性和共享性,也导致了木马、黑客、计算机病毒等恶意程序的入侵,给计算机安全甚至计算机使用者的人身安全、财产安全都带来了极大地威胁,因此应对计算机网络安全漏洞势在必行.本文就目前计算机网络安全问题进行了分类并分析了其成因,还探讨了一些针对计算机网络安全问题的解决方案,为大家提供一定的借鉴意义.     

ERW直缝焊管内毛刺清除装置的发展

简述了ERW直缝焊管清除内毛刺的方法及设备构成;重点介绍了内毛刺清除装置尤其是刀架的发展进程,在使用过程中经常会发生的问题及消除方法;同时还指出了未来发展方向。     

面向RPST的氩氮等离子射流温度分布的测量

在假定等离子体处于局域热力学平衡与光学薄条件下 ,用谱线绝对强度法测量了在等离子熔射快速制模(RPST)过程中氩氮等离子射流的温度分布。实验由CCD装置采集等离子射流图像 ,通过标定实验建立射流图像灰度和辐射强度之间的函数关系并应用Abel变换最终得到射流的温度场分布。获取的温度场将为RPST熔射工艺的合理设计提供科学依据     

Thermal press curing of advanced thermoset composite laminate parts

An alternative process to autoclaving, called Thermal Press Curing (TPC), is proposed, whereby an uncured composite laminate is pressed between a heated curing mold and customized rubber-faced mold that are designed to provide uniform temperature and pressure conditions. TPC was demonstrated by designing a complex 3-D ‘benchmark’ part shape, applying a simple computational algorithm to derive the required tool shapes, and fabricating the tooling. A comparative study was performed involving the benchmark part made from four plies of woven carbon/epoxy prepreg material. Identical laminates were pre-formed by double diaphragm forming and then cured and consolidated by autoclaving, Quickstep, and TPC using standard industry practice. Results of the study indicate that the TPC part is of similar quality as compared to those made by autoclaving and Quickstep, but, more importantly, requiring significantly less energy and resource consumption, lower cost (capital and recurring), and less preparation and cycle time.     

一种“一面两孔”定位销设计方法

提供一种在夹具设计实践中总结出来的定位销设计方法,该方法简单有效,有别于传统夹具教材和手册上介绍的定位销设计原理。其基本过程是,根据常用定位销的配合间隙和工件定位孔公差,计算出两定位销允许的中心距公差。这种新的设计方法为合理确定夹具设计精度提供依据。给出了标准定位销和变型定位销不同结构形式和典型实例,对灵活使用定位销具有较高参考价值。     

基于TeamCenter Engineering的飞机工装语义协同设计技术研究

针对飞机工装协同设计特点和难点,结合当前国内航空制造企业现状,分析了实现飞机工装语义协同设计的必要性。在对飞机工装协同设计中语义信息的相关性传递情况进行研究的基础上,提出了基于TeamCenterEngineering的飞机工装语义协同设计技术实现框架及其关键技术,该技术实现框架已在某航空制造企业得到成功应用实施。     

On the proper characterization of tooling motions and initial conditions in powder die compaction modeling

The present paper is concerned with the finite element modeling of Powder Metallurgy (P/M) cold die compaction process. Rather than on material constitutive theories or on numerical algorithmic issues, attention is confined exclusively on an scarcely addressed issue in the P/M modeling literature: the proper characterization of the boundary (tooling motions) and initial conditions of the problem. A case study of the compaction of an axially symmetric multilevel adapter in an advanced CNC press machine is used to convey the relevance of the accurate representation of these input data in the quality of model predictions. It is shown that unawareness or deliberate simplification of apparently insignificant details in this respect may cause errors far overshadowing those introduced by deficiencies in either the constitutive model or in the corresponding algorithmic solution procedure. The discussion of this case study serves also to provide useful modeling guidelines; illustrate frequent difficulties, as the unavailability of some information when guessing starting conditions; and reveal subtle, yet relevant for modeling purposes, technical details of advanced CNC press machines.     

快速成型和快速模具在现代工业中的应用

从快速成型和快速模具产生的历史背景开始，阐述了快速成型和快速模具的工作原理、主要方法、独有特性、重要意义和在现代工业生产中的应用。