NM3500和NM7000监控技术的差异

理解厂方为何如此设计,才能很好的维护和维修设备,必要时技术改进,有助于理解如何技术革新升级成为下一代设备NM7000的工作原理。     

单长网纸机网部成形与脱水

分析了单长网造纸机各种脱水元件的优势、劣势及特点,阐述了如何进行脱水元件的优化设计和最佳参数的选择问题。     

声学黑洞原理的双层加筋板⁃腔系统降噪研究EI北大核心CSCD

双层加筋板在现代交通运输工具中被广泛应用,这类结构的声振抑制问题一直是难点。声学黑洞(ABH:Acoustic BlackHole)作为一种新型的波操纵技术,为结构振动噪声控制提供了新思路。提出将ABH应用于双层加筋板中,开发有良好机械特性,特别是能实现减振降噪的结构。设计含有ABH的双层加筋板⁃腔系统,搭建实验平台并在点载荷激励下进行效果测试。结果表明截止频率以上腔体的宽频噪声可降低1.5~8 dB。基于有限元方法建立耦合数值模型,多角度量化了系统的动力学特性,分析揭示了ABH在腔室降噪中具有增加系统阻尼和降低内壁板和声腔的耦合强度的双重物理机制。针对降噪效果欠佳的低频段,提供优化设计方案,拓宽有效频率,实现了全频带的控制。进一步验证了复杂载荷作用下ABH双层加筋板⁃腔声振系统的减噪普适性。     

C620车床主轴系统的改造方案

将已经磨损失效的旧车床改造为性能优越的数控车床，是一个既经济实惠又能提高加工质量和生产效率的改造项目，很受中小企业的欢迎。由于这类车床制造年代较早、生产厂家不同，结构落后，配件短缺，按原设计修复比较困难，即使勉强修复，其旋转精度、传动效率和使用寿命都较低。但是，这类车床的主轴、主轴箱箱体、床身和溜板基本上是完好或可以修复的。这就为数控改造提供了主要的机械零部件。现以C620卧式车床主轴传动系统及主轴结构的改造为例概述一套成功的方案。     

简易小方孔冲模设计

在我厂生产的不锈钢冲压多级离心泵系列中,其中流量为60m3/h,单级扬程20m以下的冲压多级离心泵是全不锈钢型,其内在的叶轮、正反导叶、导流板、导流壳等均为不锈钢板材冲压、拉深成形。     

Composite with Recyclable Loads for the Manufacture of Blocks to Build Popular Houses

The science space in a state school in Natal city was built using a composite consisting of gypsum, EPS （expanded polystyrene）, shredded tire, cement and water. Mechanical and thermal resistances were evaluated. Inside the blocks, three types of fillings （EPS plates, aluminum cans and 500 mL bottles of mineral water） were placed in order to obtain a walls with higher thermal resistance, but also to give it an ecologically correct order, considering that both the tire and the EPS occupy a large space in landfills and require years to be degraded when released into the environment. Compression tests were conducted according to the rules. The experiments demonstrated that the temperature difference between the internal and external surfaces on the walls reached levels above 12.0 ℃. It was also demonstrated that the proposed composite has adequate mechanical strength to be used for sealing walls. The proposed use of the composite can contribute to reduce the significant housing deficit of Brazil, producing popular houses at low cost and with little time to work.     

火车车轮S形辐板成形研究

借助商业有限元软件MSC/Superform,数值模拟了车轮压弯成形过程。研究了车轮S形辐板成形过程金属流动规律,得到了S形辐板截面变形分布,为S形辐板车轮成形工艺设计提供依据。