精煤脱介筛激振器轴承检修的几点经验

精煤脱介筛激振器是选煤厂的关键设备,其正常工作是保证选煤厂生产必不可少的前提。但是,由于精煤脱介筛激振器工作在重载条件下,其轴承十分容易损坏,且拆卸维修十分繁琐,影响了选煤厂的正常运转。结合我厂生产中的实际情况,分析了精煤脱介筛激振器故障的常见原因和维修方法,对生产实际有着指导意义。     

试漏机常见故障诊断及维修

介绍试漏机工作原理及其主要作用,对试漏机在使用过程中的常见故障的诊断及维修作了简要分析,如气压故障、液压故障及检测仪器故障等。     

空管Thales二次雷达接收机设备原理与维修案例剖析

空管二次雷达系统是实施空中交通管制的重要设备之一。针对空管Thales二次雷达接收机设备故障频出的情况,分析了其组成、工作原理,并通过案例讲述了其故障维修的方法。相比送原厂动辄一年的维修周期,极为高效地解除了民航空管安全的保障压力,也节省了大量的维修资金。     

沃尔沃发电机组发动机“喷”机油维修

讲述沃尔沃发电机组在工作时,排气管向外部排废气的同时"喷"机油现象的故障诊断和维修过程;在检测维修中,利用分析方法,找出引起故障的原因,为发动机组的维修提供参考依据,确保维修品质。     

关于现代汽车维修新技术中电子诊断的运用分析

随着时代的发展,我国汽车维修技术正在不断进步。以往在维修过程中使用的诊断技术较为落后,不仅影响了维修效率,也影响了汽车行业的发展。使用电子诊断技术能够快速检测汽车存在的故障及问题,既能够提高维修速度,也能够提高维修质量。基于此,本文首先介绍了现代汽车维修技术的特征,然后,介绍了电子诊断技术对汽车维修产生的影响,随后从六个方面讲述了电子诊断技术在汽车维修中的具体运用,以此供相关人士交流和参考。     

医疗设备电路故障的判断方法与维修措施探究

医疗设备是现代医疗和临床学科工作中最基本的要素,是不断提高医学科学技术水平的基本条件,医疗设备已成为现代医疗工作的一个重要领域。但是,医疗设备在使用过程中,由于操作、使用、维护不当等原因,常常导致医疗设备的故障。鉴于此,本文对医疗设备电路故障的判断方法、维修步骤及措施进行了探究,目的是为了提高维修工作中的效率和专业技能。     

运用程序联机方法快速排查旋挖钻机主卷扬无动作故障

正目前旋挖钻机电控系统大都由可编程控制器及显示器组成,编程平台一般为Codesys软件。这就要求电气设计人员具备一定的编程能力,电气维修服务人员具备一定的解读能力。与运用万用电表等工具进行排查故障的传统方法相比较,运用程序联机进行故障判断,可更快、更准地找到具体故障部位,减少维修时间,提高维修质量和效率。本文以旋挖钻机主卷扬无动作故障为例,讲述运用程序联机进行故障排查的方法。     

电喷发动机故障诊断的基本原则及注意事项

电喷发动机的结构、工作原理及维修比较复杂,给故障的诊断和排除造成一定的难度.介绍维修人员应全面掌握的电喷发动机的结构及故障的诊断和排除过程中的基本原则和注意事项.     

民用直升机维修保障相关故障模式及影响分析研究

作为维修工程分析中的一种,维修保障相关故障模式及影响分析(LSA FMEA)主要面向修复性维修。通过对民用直升机维修保障相关故障模式及影响分析的基础理论、层级划分以及影响决策等因素进行深入研究,建立了一套完整的LSA FMEA分析方法和决断逻辑,以便在产品投入运营之前分析得出由于产品内在固有故障特征而必然导致的修复性维修需求。     

动向记录仪故障排除方法

本文简要介绍了动向记录仪的基本原理和发展动向,重点讲述这类微机化仪器故障的诊断维修方法。文中以日本武田理研TR2723为典型例子,总结出几种非常实用的维修方法,画出了维修流程,给出了常见故障的判断及处理。     

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...     

Quantum Cooperative Robotics and Autonomy

The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci...     

考虑进油孔有限长滑动轴承油膜力的近似解析解

针对具有进油孔的有限长滑动轴承油膜力求解问题,采用变分原理和分离变量法,求得了有限长滑动轴承油膜压力分布的近似解析表达式。将油膜压力分布的近似解析表达式在油膜存在区域上进行积分,即得到了油膜力。将提出的计算有限长滑动轴承油膜力方法与无限长轴承模型、有限元方法的计算结果进行了比较,发现了提出的方法与有限元方法的计算结果很接近。最后,研究了进油孔位置和进油压力对油膜存在区域、油膜力等的影响,研究结果表明进油孔位置和进油压力对油膜存在区域和油膜力有较大的影响。     

三绕组变压器的双绕组等效建模及在Matpower中的应用

针对实际电网存在着大量的三绕组变压器,但国际上一些著名商业软件,如BPA仿真软件、Matpower这一权威潮流计算开源软件,均只提供双绕组变压器模型,限制了其在具有三绕组变压器的电力系统中的应用的问题,潮流计算是自主开发的电力系统各种应用软件的核心模块,因此依托国际权威开源程序进行二次开发,是一种较好的选择。对Matpower要求的数据格式进行了归纳,对变压器的一般的等值电路及带理想变压器的等值电路和带标幺值的等值电路进行了分析研究,提出了三绕组变压器转换为双绕组等效模型的建模方法,使得原先只适应双绕组变压器的潮流计算软件可以适用于三绕组变压器电网的潮流计算;最后以Matpower软件为例进行了案例计算,并用PSASP仿真软件进行对比验证。研究结果证明,所提出的建模方法是有效的。     

On the Relation of Load to Average Gap in the Contact Between Surfaces with Longitudinal Roughness

A computer simulation model for the contact between longitudinally-oriented rough surfaces has been formulated. This model closely duplicates the actual surf ace contact deformation behavior by taking into account the elastic interactions between the asperities. There were no assumptions made about the shapes, or any deformation behavior of the asperities, except for their obeying the laws of elasticity. The plastic deformations on the high asperity peaks were taken into account by setting a ceiling on their contact pressures at the material hardness value. The simulations used real surface profiles which were digitized from unworn circumferentially ground steel surfaces. Each pair of these profiles was mathematically combined to form an equivalent rough profile pressing against an infinitely rigid flat and having the appropriately adjusted elastic modulus. A total of 28 different pairs of profiles were used in the simulations. Each contacting pair was subjected to 30 different load levels and the local contact pressures and deformations were calculated. The contact simulations yielded some important mathematical relationships between parameters, such as the real area of contact, average gap, and average asperity load through statistical curve fitting. Two analytical functions were generated to relate the average load to average gap and the real area of contact to load.     

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.     

电站锅炉模糊风险评价方法研究与应用

针对电站锅炉风险等级评价问题,将模糊综合评价技术应用到电站锅炉风险等级评价中。开展了电站锅炉失效影响因素及模糊评价因素的重要程度分析,建立了一套科学合理适于在线评价的电站锅炉风险评价体系,提出了模糊综合评价技术与改进的模糊层次分析法相结合的模糊风险评价方法,利用改进的模糊层次分析法计算了指标体系中各层指标权重。对某一台电站锅炉的实际运行工况影响子因素进行了模糊风险评价,采用模糊合成算子进行模糊综合运算得到电了站锅炉运行工况影响子因素的评价向量。研究结果表明:电站锅炉的运行工况影响子因素的风险评价等级为第6级,失效可能性等级为小,该电站锅炉运行工况良好。     

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.     

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....