离心式压缩机的振动故障分析

介绍了离心式压缩机的振动故障特征，通过对压缩机的振动特征测试，分析振动特征和利用频谱特征求得压缩机异常振动处的频谱，找出振动的原因，并制定了合理的处理方法，彻底地解决了压缩机的振动问题。     

氨制冷螺杆压缩机的振动故障分析与治理

通过对压缩机的振动特征测试,分析振动特征和利用频谱特征求得压缩机异常振动处的频谱,找出振动原因,并制定了合理的处理方法。     

往复压缩机管道振动测试分析

利用PL302双通道数据采集器对某装置4台往复压缩机管道系统进行了振动测试,采用能量分析法发现四号压缩机管道振动最强烈;并着重对四号压缩机管道的振动进行了频谱特征分析,确定了振动的原因是气流脉动引起管系共振,需有针对性地采取减振改造措施。     

6HHE-VE-6型压缩机出口管系振动测试与分析

本文主要介绍应用智能信号采集处理分析系统，对某化肥公司6HHE-VE-6型压缩机出口管系的振动状态进行了现场实测，通过时域分析和频谱分析，得到了该压缩机的振动振幅值和振动的频率成分。同时利用有限元方法对此管道系统进行了结构模态分析，找出了管道剧烈振动的原因，并提出一套减振方案。     

K-5101/A压缩机管道振动分析及改造

针对某炼油厂的一台往复压缩机管网振动十分强烈的情况,通过对管道气体动力特征和管道结构的动力响应的分析,并结合振动测试和频谱分析,找到了管道振动的主要原因,提出了减小压力脉动的方法,并制定了有效的减振措施.管道经改造后振动有明显减小,保障了机组的高效安全运行.     

大型压缩机管道系统振动现场测试与故障分析

为了分析大型压缩机管道系统的振动故障，对某油田大型压缩机管道系统进行了现场测试和现场模态实验。利用振动测试与实验模态分析的方法，得到了压缩机管道系统振动分布情况和关键部件的固有频率、阻尼比和相应的模态振型，评估了管道系统的振动情况，分析了产生振动的原因。所得实验数据和分析结果对大型压缩机管道系统的动态设计、改造、监测与运行管理具有指导意义。     

往复压缩机管道振动测试分析

针对往复压缩机管系的振动进行了测试,得到振动位移数据和频谱特征,计算了该管系的气柱固有频率和结构固有频率,通过分析得到振动原因。并从削减激振力强度和优化管道动力特性两个方面阐述了减振措施。     

基于LMS Test．1ab的压缩机管道振动测试与分析

提出了应用LMS Test．1ab进行往复压缩机管道振动测试的新方法，利用LMS Test．1ab数据采集、分析软件及相关硬件，搭建了往复压缩机管道振动测试系统，对管道系统的固有频率进行了测试，并对测试结果进行了验证，从而证实了本系统的准确性与实用性。     

基于LabVIEW的涡旋压缩机的振动特性分析

利用虚拟仪器技术和频谱分析等信号处理的方法,使用图形化虚拟仪器编程软件LabVIEW及相关硬件产品,完成了涡旋压缩机振动测试系统,通过对涡旋压缩机进行现场采集来的数据分析处理,证实了本系统的有效性.     

瓦斯气压缩机排气管道振动原因分析

通过对该瓦斯气压缩机振动的测试与分析，找出．了该机振动的主要激励源和主要影响因素，进而对该机的管路系统进行了管系气柱固有频率、气流脉动、管系结构固有频率、管道振动响应及管道动应力的分析计算；并对改进前后的振动参数作了比较，改进前后参数变化明显。根据分析结果．对该压缩机级管路系统的减振问题进行了改进，改进效果显著。     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...     

End-to-End Multiview Gesture Recognition for Autonomous Car Parking System

The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods....     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

ANGULAR DISTORTION ALLOWABLE VALUE AND ASSESS METHOD OF WELD ON COKE TOWER

A graph as the new engineering method for estimate the safety of bulging deformation of coke tower is proposed. Through stresses analysis of circumferential weld of coke tower and comparing the stresses produced by pressure with heat stress of steady state, residual stress, bending stress produced by both itself weight and wind loads, it showed that the stresses produced by pressure on the angle distortion are the main factor of equivalent stress of the combined stress. After comparing four kinds of stress controlling conditions, the relation to stress with depth of angular distortion, grade of curvature of angular distortion and half of region of angular distortion has been inferred. Graph of deformation allowable value of coke tower for different condition by angular distortion and half of region of angular distortion has been plotted. The five steps for its engineering use have been explained. The lighter the grade of curvature is, the larger of bulge allowance, may be, and the bigger of depth of angular distortion may pose too. For the coke tower with a popular structure of Dg 5 400 mm×28 mm, the result by graph is nearly more than the result of two formulas formed by other research, the error is less than 7.0%. But, the graph can be easily applied to different size of angular distortion.