On the use of intrinsic fluorescence emission ratio in the characterization of hydraulic oil degradation

Intrinsic fluorescence emission of oil was used to develop a technique and detector for evaluating oil degradation. Test results for hydraulic oils with and without zinc dialkyldithiophosphates additives and calcium-based dispersant were in conformance with the results of optical emission spectrometry, particulate counts, optical microscopy, total acid number, and viscosity tests. The ratio of intrinsic fluorescence emission was found to be a parameter independent of the concentration of dust and iron contaminants in non-additive oil. It proved to be dependent on oil chemical degradation, becoming a tool to detect degradation before incipient wear at the tribological interface becomes relevant. The study showed that intrinsic fluorescence emission ratio gives sufficient information to characterize and evaluate oil degradation.     

基于PCA的时间分辨油荧光光谱分析及优化

激光诱导荧光技术可广泛应用于油污染的监测中,然而普通的油荧光光谱技术只能实现油污染监测的粗分类,无法区分原油与燃料油的荧光特征。本文基于主成分分析方法(PCA)的时间分辨油荧光分类方法,实验测量了20种油样本的时间分辨荧光光谱特征,给出了对应的荧光寿命和时间分辨油荧光光谱的时序特征。在此基础上,利用前三个主成分构成的三维特征矢量空间,通过分析不同采集时刻下油样本矢量间相关距离的变化,对油样本的时间分辨荧光光谱进行聚类分析。为了体现油荧光变化的时序性,引入矢量距离的离散度参量,提出基于PCA进行时间分辨油荧光光谱分析的优化方法。实验结果表明,基于时间分辨油荧光光谱识别可实现原油与燃料油的光谱时序特征区分,具备良好的油荧光分类效果。     

X射线荧光光谱法测定抗燃油中氯含量的不确定度评定

本文介绍了X射线荧光光谱法检测磷酸酯抗燃油中氯含量的原理,分析了测量过程中不确定度的来源,并对其测量不确定度进行评定,为日后相关工作的开展提供宝贵的数据支撑。     

在线荧光测油仪的研制

采用近现代紫外荧光测量技术,针对水质常规检测指标,围绕水环境质量在线监测、水污染事故应急监测、水环境污染源监测等方面需求,研制水中油在线荧光分析监测产品;仪器采用模块化结构设计,双光路、双通道、双测量采样、嵌入式系统控制、数据自动采集、存储和发送。采用低功耗255nm的LED灯激发光源,光电倍增管作为荧光检测器,可以检测水面表层至10m水深的油品含量。创新的采样流路设计,可有效地避免日光对测量的影响,及有效地清除长期使用过程中水中物质对流路的污染。     

Manufacturing and use of novel sensoric fasteners for monitoring forming processes

This paper presents sensoric fasteners which are produced by metal forming. Sensoric fasteners enable the monitoring of pretensioning forces and operating loads in mechanical connections between components. For the gathering of combined force and torque sensor signals in individual spatial directions the sensor unit has to provide the capability to transmit loads in all directions of space. The elementary sensors are integrated into the metallic fasteners structure during manufacture. This results in an assembly of supporting structure and sensor which shows a highly reproductive and sensitive interaction between its mechanical and electrical properties. In order to evaluate this interaction calibration measurements are carried out.With the help of examinations of both stationary and transient running manufacturing processes it can be shown, that the new fasteners provide the mechanical connection between tools and machine as well as the possibility to monitor operating loads. The latter allows monitoring and analysis of process forces acting within the mechanical connections.     

智能变压器绕组热点温度监测仪

本文介绍了一种新型油浸式电力变压器绕组热点温度在线监测仪。该监测仪实时采集变压器负荷电流和变压器顶层和底层油温,依据国际电工技术委员会推荐的油浸式电力变压器绕组热点计算公式,实时监测绕组热点温度。文中介绍了监测仪的测量原理及硬件电路和软件流程,给出使用后的数据记录。结果表明,该监测仪的稳定性与精度均满足现场测试要求。     

500kV变压器油自动取样装置

近年来国内电网500 kV变压器数量迅速增加,采用传统的变压器油取样方法,500 kV变电站主变/电抗器在进行色谱、含气量普查中,因取样不合格而需要复查的现象时有发生。针对500 kV变压器油取样失真的问题,设计了一套自动取油样装置,给出了取样油、氮气管路设计方案以及基于单片机技术的控制系统设计方案;同时,分析了几种因素对于取样精度的影响。研究结果表明,该装置能够实现500 kV变压器油的高精度、高真空度、高清洁度的自动取样,且操作简便快捷。     

Production of a transformer oil from paraffinic basestocks

The work described in this paper is concerned with the production of a high quality transformer oil from local Egyptian paraffinic basestocks. Analysis showed that a neutral base oil 70N was most suitable for producing transformer oils. This neutral base oil was chemically treated with a sulphonation process. Optimum sulphonation conditions were achieved by using oleum or SO₃ at a concentration of 6 wt. %. The sulphonation reaction was carried out in three stages, each with an equal portion of the sulphonating agent. The acidic oil was then neutralised with an alkaline solution. Oil colour improvement was effected using activated clay as an absorbent. Laboratory results and field trials indicated that such a treated neutral paraffinic oil meets the IEC 296 international specifications for transformer oils, with the exception of pour point (−12°C). However, such a pour point is not relevant in certain hot climatic conditions. Comparative evaluation of the treated oil with commercial transformer oils has shown its suitability.     

绝缘油介电强度测试仪的设计

介绍了单片机控制的绝缘油介电强度测试仪的工作原理、硬件电路及软件设计,并在硬件电路设计中注意了系统的抗干扰问题;采用了555定时器电路切断高压电源,解决了高压击穿时长时间放电干扰现象;试验表明,该仪器能够较好的完成要求的测试功能,而且测试数据准确可靠,性能稳定.     

An investigation of acoustic emission to monitoring flat lapping with non-replenished slurry

Lapping is a precision manufacturing process. However, the material removal rate and surface roughness show significant variation between trials for repeated experiments and, thus, the repeatability of the results depends on the machine operator’s skill. Acoustic emission (AE) seems to be capable of monitoring the process. Therefore, an understanding of AE generation during lapping is important to predict the performance of the grains and hence the lapping results. Based on a theoretical analysis and experimental results collected during flat lapping, the AE signal was investigated for the situation when slurry is supplied without replenishment. The experiments were carried out with a wireless rotating AE sensor mounted in the middle of the lapping plate. Three parameters related to the AE curve are proposed to monitor the process. The influence of process parameters (lapping pressure, velocity, average grain size, concentration of grains in lapping compound and the number of conditioning rings) on the characteristics of the AE curve was investigated.     

原油含水率的检测及原油计量的研究与实现

以油田集输工艺中的沉降罐为对象,采用差压变送器和液位变送器为检测手段。应用计算机进行在线处理,实现了沉降罐原油含水率的在线检测及原油的精确计量。     

A 3D aligning method for stimulated emission depletion microscopy using fluorescence lifetime distribution

Optimal resolution by stimulated emission depletion (STED) microscopy requires precise alignment of the donut‐shaped depletion focus to the excitation focus. In this article, we demonstrate that fluorescence lifetime distribution can be implemented to align the STED system. Different from the traditional aligning methods in which a scattering imaging module is often equipped, the lifetime‐based method is free from probable mismatches between the scattering mode and the fluorescent mode, drift errors caused by separate imaging and complex fitting methods. Based on this method, a spatial resolution of 38 nm by time‐gated detection has been achieved. Microsc. Res. Tech. 77:935–940, 2014. © 2014 Wiley Periodicals, Inc.     

Sensitivity of RF Sensors for Bearing Health Monitoring

Coated bearings in high-performance turbine engines have the potential to provide considerable improvement in engine reliability and service-life extension. One coating performance indicator is the level of vibration generated by rolling elements and their cage separators at high-speed bearing operation. This article introduces a nonintrusive, cage-mounted sensor that detects cage vibration and transmits wirelessly to a nearby receiver. The sensitivity of the cage-mounted sensor was compared to a housing-mounted accelerometer in the detection of seeded faults in coated and uncoated bearings. The smallest spall on an uncoated bearing that the sensor could detect was 28 μm deep × 3.2 mm wide, with a reliability of ～40%. In contrast, the accelerometer consistently detected all levels of flaws, the smallest being 0.4 μm deep × 3.2 mm wide on the coated bearing, with a reliability of 55%. Despite the sensor having a detection rate less than the accelerometer, this research successfully demonstrated that the sensor could detect inner-race-bearing flaws and established its sensitivity level.     

无线加速度传感器的MEMS芯片ADXL202应用设计与集成

阐述了一种基于MEMS技术的芯片ADXL202的应用设计与集成。介绍了ADXL202的测试原理和主要参数设计原则，然后利用其集成了一种无线加速度传感器并进行了测试。实验结果表明：ADXL202非常适合于频率变化较为缓慢、加速度不太大的土木工程结构的测量；利用ADXL202所构成的无线加速度传感器，易安装拆除，适合在土木工程结构监测中应用。     

Fluorescent express-method for monitoring of oil condition in tribosystems

Current interest in evaluating the oil condition in tribosystems is discussed. Fluorescent express-methods for oil condition monitoring are analyzed and their main advantages and disadvantages are noted. The basic concept of the fluorescent method developed for evaluating oil oxidation rate by recording the shift of fluorescence spectrum to the long-wave region is described. The realization of the method is exemplified and the results of the analysis of fresh and worked hydraulic oils with the developed fluorescent sensor are given. The sensor can be used as both built in the oil line and a portable device under manufacture and laboratory conditions.     

掠出射X射线荧光分析技术与掠入射X射线荧光分析技术

依据工作原理,比较了掠出射X射线荧光分析技术(GEXRF)和掠入射X射线荧光分析技术(GI-XRF)的优缺点,比较角度包括实验装置、探测限、可探测元素范围、基体效应以及实验精度.比较结果表明,GEXRF的优点体现为:对实验装置要求低,对轻元素(4＜Z＜20)特别灵敏,能对大样品进行检测,实验精度高;缺点体现为:临界厚度小,探测限高."对轻元素特别灵敏"的特点决定了GEXRF的应用领域将主要集中在化学元素微量和痕量分析以及半导体工业中Si薄膜表面轻元素检测等方面.     

Analysis of condition monitoring methods for electromotor on oil platform

Electromotor on oil platform often has mechanical failures.In order to achieve monitoring and diagnosis of the electromotor,common diagnostic methods of electromotor are summarized first,and then vibration monitoring is regarded as a suitable method for monitoring and diagnosing of mechanical failures by comparing the advantages and disadvantages of each method and characteristics of mechanical faults.At last,the fault frequencies and arrangements of vibration measuring points are analyzed.By using vibration monitoring method,the diagnosis of bearing faults of electromotor is carried out.The results show that the analysis of condition monitoring methods for electromotor is meanning for machine maintenance and repair,and it lays foundation for computerized repair system and resource management system.     

基于GPRS的油田抽油机远程在线监控系统的设计与实现

介绍了基于GPRS的油田抽油机远程在线监控系统,其中对系统结构、工作原理、硬件构成及软件设计进行了比较详尽的论述。该系统实现了对油田抽油机多种工作状态参数的现场检测、远程传输和集中处理,并可及时发现、消除由于抽油机故障引发的油田作业缺陷,对确保油田的安全生产具有十分重要的意义。实践证明该系统运行稳定、可靠。     

An electrical impedance monitoring method of water-lubricated oil transportation

We propose a simple and efficient monitoring system based on a single-drive interleaved electrode impedance technique that provides cross-sectional images for real-time detection of fouling in oil–water flows. The simple monitoring method is proposed using a data-interface formula relating between voltage differences measured at sensing electrodes and interfaces of the two immiscible fluids in a pipeline. We estimate the minimum distance between the interface and pipe wall at the images, that is an indicator for monitoring the fouling, by using a voltage–distance map. The robustness of the proposed method is validated through various numerical simulations including oil–water flows in an U-bend return pipe.     

一种军械油料快速检测方法研究

本文采用YX1154油料电导率测定仪研究了组分变化对45号变压器油和通用装备液压油两种油料电导率的影响，探索了电导率与传统测试指标的相关性。结果表明：油料电导率随防锈剂含量变化呈线性增加，并且与抗腐蚀性能测定结果一致。因此，该方法不仅可用于军用油料的生产质量检测和库存质量监控，而且可作为野战条件下评价油料性能的快速检测方法。