机组氢气纯度频繁下降的原因分析与处理

针对某U600MW超临界机组氢气纯度频繁下降进行了原因分析,确定了氢气纯度下降的原因为密封瓦及油挡与发电机大轴间隙过大,导致空、氢侧密封油交换量大,制定了相应的防范措施,并在大修中得到了处理,取得了很好的效果。     

发电机氢气纯度下降的原因分析及治理

针对马鞍山当涂发电有限公司#1机组发电机氢气纯度下降的问题,通过对影响因素进行全面分析,找到了影响氢气纯度的真正原因并加以解决。     

希尔伯特-黄变换轴瓦异响故障诊断

根据汽车发动机信号非线性、非平稳性特点,分别对正常以及轴瓦异响发动机信号进行HHT,得到希尔伯特谱与时频分布三维图。将引起异响的高频成分从异响信号中分离,再通过对高频成分的分析找出故障原因。结果表明,正常发动机固有频率为210Hz,轴瓦异响发动机频率主要集中在500,1 500和2 700Hz,通过对比加速度谱分析结果,判断出轴瓦异响的原因是轴瓦磨损。     

浅谈丁基胶垫与气门嘴的粘合

本文介绍了丁基橡胶垫与铜制气门嘴粘合的有关问题，并提供了解决方法。     

Stochastic Models for Pad Structure and Pad Conditioning Used in Chemical-Mechanical Polishing

Stochastic models are presented for the structure and conditioning of pads used in chemical-mechanical polishing of wafers. First the one-dimensional distribution function of surface depth in the case of a conditioned solid pad is described. Then, for characterizing the structure of a foamed pad, the theory of random closed sets is applied. An important distributional characteristic of a random closed set, the linear contact distribution function, yields the contribution to surface depth resulting from pores. As a special example the Boolean model is considered. This leads to a formula that describes the variability of the surface of a conditioned foamed pad after a certain time. Simulations and experimental data show a good agreement between theory and reality.     

The Post-Yield Behaviour of an Internally Pressurised Cylinder having a Pad Attachment

Abstract:  A study of pressurised cylinders having attached pads was made. The possibility of a fatigue crack developing along one side of the pad was noted. For both defect-free components and components having axial crack-like defects, finite element and limited experimental studies of the local and global deformations were made and results were found to be in close agreement. Both welded and integrally machined pads were studied. It was observed that for defect-free components, the method of pad attachment has little effect on the burst pressure. The presence of a pad was found to increase the burst pressure of cracked components by a small but significant margin. A finite element-based parametric study of pipes with part-penetrating defects and a range of pad geometries has demonstrated that pad size has little influence on the limit load for any of the cracked cases considered. However, pipes with penetrating defects were strengthened by the presence of pads, particularly for thin-walled sections.     

条格面料男西服的肩线及驳领部位结构处理方法探究

条格面料男西服的品质优劣，很大程度上取决于各部件之间的组合是否条格相对，这不仅是排版与制作时要注意的，更多的准备工作要在制版中完成，文章从结构设计的角度对西服的关键部位加以论述，较好地解决了西服肩部及驳领的对条格问题。     

大型低速重载径向动压轴承研究

为了开发大型贯流式水轮发电机组径向轴承，在试验台上采用了φ360的模型轴承对φ1740可倾6瓦块原型轴承进行模拟试验研究，最高试验比压3．37MPa、最低线速度3．77m／s、最高线速度22．62m／s。试验表明：载荷、进油压力、转速、进油温度和安装间隙比等，对轴承油温升、油流量、功耗、瓦温及油膜厚度等都存在不同程度的影响，其中载荷和转速的影响比较显。按照模型轴承指导设计的红岩子机组书φ1740轴承已在电站可靠运行，同时开发了径向轴承热弹流计算程序，可以预测径向轴承的油膜压力、油膜温度、油膜厚度、损耗、流量等参数。     

硅微条探测器

硅微条探测器的位置分辨率可好于σ＝1．4μm，这是任何气体探测器和闪烁探测器很难作到的。主要介绍硅微条探测器的特点、结构、工作原理及其在近年来的发展和在高能物理、核医学等领域应用概况。     

一种棒材计数装置的研究

介绍了棒材在线计数的意义和这一技术的进展，详细分析了影响摄像技术采集棒材特征的各种因素和干扰，研制成功了棒材在线计数装置并获得国家专利。装置在线采集链条上每组棒材端面的图像，经计算机进行图像识别，实现了各种规格棒材在线的精确计数。装置的创新点：数据采集箱用于隔离外界干扰；快速准确的图像识别算法；喷液装置使端面成像易于被识别；采集的数据参与过程管理。