Design on Vibration Monitoring and Fault Diagnosis System of Large Water Pump Motor

Large water pump motor,whose operation decides the reliability of the whole production line,plays a very important role.Therefore,its online condition monitoring can help companies better know its operation,process fault analysis and protection.The essay mainly studies and designs large water pump motor′s real time vibration monitoring and fault diagnosis system.The essay completes the systems project design,the establishment of the system and performance test.Eddy-currentsensor,XM-120 vibration module,XM-320 axial translation module,XM-362 temperature module,XM-360 process amount module and XM-500 gateway module are used to measure the axial vibration and displacement of main motors.Laboratory tests prove that the system can meet the requirements of motor vibration monitoring.

Label-Free and Real-Time Monitor of Binding and Dissociation Processes between Protein A and Swine IgG by Oblique-Incidence Reflectivity Difference Method

Life science has a need for detection methods that are label-free and real-time. In this paper, we have selected staphylococcal protein A （SPA） and swine immunoglobulin G （IgG）, and monitor the bindings between SPA and swine IgG with different concentrations, as well as the dissociations of SPA-swine IgG complex in different pH values of phosphate buffer by oblique-incidence reflectivity difference （OIRD） in a label-free and real-time fashion. We obtain the ON and OFF reaction dynamic curves corresponding to the bindings and dissociations of SPA and swine IgG. Through our analysis of the experimental results, we have been able to obtain the damping coefficients and the dissociation time of SPA and swine IgG for different pH values of the phosphate buffer. The results prove that the OIRD technique is a competing method for monitoring the dynamic processes of biomolecule interaction and achieving the quantitative information of reaction kinetics.

Fatigue damage reliability analysis for Nanjing Yangtze river bridge using structural health monitoring data

To evaluate the fatigue damage reliability of critical members of the Nanjing Yangtze river bridge, according to the stress-number curve and Miner’s rule, the corresponding expressions for calculating the structural fatigue damage reliability were derived. Fatigue damage reliability analysis of some critical members of the Nanjing Yangtze river bridge was carried out by using the strain-time histories measured by the structural health monitoring system of the bridge. The corresponding stress spectra were obtained by the real-time rain-flow counting method. Results of fatigue damage were calculated respectively by the reliability method at different reliability and compared with Miner’s rule. The results show that the fatigue damage of critical members of the Nanjing Yangtze river bridge is very small due to its low live-load stress level.

Measuring Vibration of Body with Speckle Interferometry

Speckle interferometry is an efficient method to analyze a vibration. In certain conditions, this technique has some outstanding advantage, and need not strict shock--proof condition, compared with the holographic method for measuring vibration. Therefore,it is suitable to analyze a vibration with a large amplitude.Real-time interferometry is a rapid and simple method for measuring vibration of a body, gives speckle pattern containing amplitude distribution of body-surface. By means of time-averaged method, the speckle pattern is recorded in Fourier transform plane, or vibration lines are seen directly with eyes, so as to analyze efficiently amplitude, phase, and model of a vibration. This paper deduces the intensity distribution function with real-time method, and gives experimental demonstration of vibration body-the vibration lines with different frequencies.

预留核心土法隧道爆破围岩损伤与振动特性研究

目的 研究预留核心土法爆破开挖影响下的山岭隧道围岩损伤与振动特性,为爆破参数优化以及隧道加固设计提供理论参考。方法 依托新疆阿克特蒲2号左洞隧道工程,借助ANSYS/LSDYNA软件建立隧道爆破开挖数值模型,基于现场实际开挖轮廓和振速监测数据验证数值模型的合理性,进而分析围岩累积损伤特性、振速分布和振速衰减规律。结果 爆破结束后,隧道轮廓平整,预留核心土上部损伤严重;隧道拱顶y方向、拱肩z方向及拱脚x方向的振速最大;距离掌子面越近,采用萨道夫斯基经验公式预测的振速结果误差越大。结论 为保证结构稳定性,在下次爆破施工前可以通过减少掏槽孔、辅助孔的装药量或者调整其孔网参数来减小爆炸荷载,沿最大振速方向进行重点加固;采用萨道夫斯基经验公式预测距离掌子面10 m内的振速时,避免仅用z方向距离近似为爆心距大小,应同时考虑三个方向的距离。

Virtual sensing method for monitoring vibration of continuously variable configuration structures using long short-term memory networks

Vibration monitoring by virtual sensing methods has been well developed for linear timeinvariant structures with limited sensors.However,few methods are proposed for Time-Varying(TV)structures which are inevitable in aerospace engineering.The core of vibration monitoring for TV structures is to describe the TV structural dynamic characteristics with accuracy and efficiency.This paper propose a new method using the Long Short-Term Memory(LSTM)networks for Continuously Variable Configuration Structures(CVCSs),which is an important subclass of TV structures.The configuration parameters are used to represent the time-varying dynamic characteristics by the‘‘freezing"method.The relationship between TV dynamic characteristics and vibration responses is established by LSTM,and can be generalized to estimate the responses with unknown TV processes benefiting from the time translation invariance of LSTM.A numerical example and a liquid-filled pipe experiment are used to test the performance of the proposed method.The results demonstrate that the proposed method can accurately estimate the unmeasured responses for CVCSs to reveal the actual characteristics in time-domain and modal-domain.Besides,the average one-step estimation time of responses is less than the sampling interval.Thus,the proposed method is promising to on-line estimate the important responses of TV structures.

基于经验模态分解的火力发电厂锅炉给水泵振动故障监测

常规的给水泵振动故障监测方法以振动故障分布特征分析为主,受到给水泵运行环境的影响,故障监测存在失误的问题。因此,文章设计了基于经验模态分解的火力发电厂锅炉给水泵振动故障监测方法。提取火力发电厂锅炉给水泵振动信号特征,采集锅炉给水泵的振动信号,反映水泵在不同频率的故障状态。基于经验模态分解构建给水泵振动故障监测模型,利用经验模态分析处理给水泵振动信号,得到IMFs幅值、频率、能量分布等参数,进一步表征给水泵振动故障状态。在线监测发电厂锅炉给水泵振动效率,设置给水泵振动效率阈值,评估给水泵的振动异常情况,从而避免故障监测失误的问题。采用对比实验,验证了设计方法的故障监测准确性更高,能够应用于实际生产中。

煤矿通风机振动故障预警方法设计及应用研究

针对通风机振动故障预警存在的不足,对煤矿井下恶劣工作环境中通风机机械典型故障及其特征进行分析,阐述了振动分析方法及其基本规范,设计了一种创新的基于振动分析的煤矿通风机振动故障预警方法。该方法以MCM-100设备状态监测平台为基础,603C01加速度振动传感器对振动信号进行高精度在线动态采集,运用频谱分析+振动强度对故障进行诊断识别。实践结果表明:该通风机振动故障预警方法能对永红煤矿FBD8.5-2×75型局部通风机发生的所有振动故障进行准确判断,并进行预警,保障了设备的安全,为煤矿通风机的故障监测与预警提供了一种有效的技术解决方案,有助于提高煤矿的安全性和效率。

基于振速法和1/3倍频程谱的座椅噪声评定系统研究

国内汽车座椅噪声检测主要是在环境噪音不超过30dB左右的消声室中采用声级计进行检测,其建设成本高、检测效率低,不适宜工业现场生产。文章基于振速法获取噪声数据,该方法测试时可避免工业生产现场的背景声和反射声干扰。通过1/3倍频程谱方法缩小频率分析范围,并对各个频带的声功率级进行叠加处理后进行分析评定。系统硬件由成本较低的加速度传感器、电荷放大器、数据采集卡和上位机等部分搭建,经测试证明该系统运行效率高、监测评定数据可靠。该在线监测评定系统提升了汽车制造企业生产效率、降低生产成本、提升汽车制造性能,可广泛推广到汽车生产企业制造生产线中。

Application of clan member signal method in structural damage detection

It is well known that in most cases, a reference is necessary for structural health diagnosis, and it is very difficult to obtain such a reference for a given structure. In this paper, a clan member signal method （CMSM） is proposed for use in structures consisting of groups （or clans） that have the same geometry, i.e., the same cross section and length, and identical boundary conditions. It is expected that signals measured on any undamaged member in a clan after an event could be used as a reference for any other members in the clan. To verify the applicability of the proposed method, a steel truss model is tested and the results show that the CMSM is very effective in detecting local damage in structures composed of identical slender members.

Cross spectral energy method for damage assessment of the cable-stayed bridge under operational conditions

The new cross spectral energy method(CSEM)is proposed for maintaining cable-stayed bridge safe-ty by the measurable output-only vibration response.Damage assessment of real structures is limited by aseries of problems such as unknown ambient excitation forces,errors introduced by system identification,incomplete dynamic measurements,etc.Thus the methodology based on cross spectral energy of eachsubstructure member is derived to meet these challenges.The novel damage index does not require anymodal or parameter identification technology.It can be calculated directly from vibration test data.In or-der to evaluate the efficiency of the presented methodology,a three dimensional(3D)actual cable-stayedbridge model with one or more damaged positions under operational conditions was studied.In order totestify the reliability of damage detection method,the response data was polluted by the random noise.Itis proved that the proposed method can successfully localize all damage cases even in noisy data.Withthe help of examples,the CSEM can potentially be applied as a nondestructive evaluation technique(NDT)for on-line health monitoring of cable-stayed bridges with minimum disruption of its operations.

Automated monitoring and warning solution for concrete placement and vibration workmanship quality issues

Placing and vibrating concrete are vital activities that affect its quality.The current monitoring method relies on visual and time-consuming feedbacks by project managers,which can be subjective.With this method,poor workmanship cannot be detected well on the spot;rather,the concrete is inspected and repaired after it becomes hardened.To address the problems of retroactive quality control measures and to achieve real-time quality assurance of concrete operations,this paper presents a monitoring and warning solution for concrete placement and vibration workman-ship quality.Specifically,the solution allows for collecting and compiling real-time sensor data related to the work-manship quality and can send alerts to project managers when related parameters are out of the required ranges.This study consists of four steps:(1)identifying key operational factors(KOFs)which determine acceptable workmanship of concrete work;(2)reviewing and selecting an appropriate positioning technology for collecting the data of KOFs;(3)designing and programming modules for a solution that can interpret the positioning data and send alerts to project managers when poor workmanship is suspected;and(4)testing the solution at a certain construction site for validation by comparing the positioning and warning data with a video record.The test results show that the monitoring performance of concrete placement is accurate and reliable.Follow-up studies will focus on developing a communication channel between the proposed solution and concrete workers,so that feedbacks can be directly delivered to them.

桥梁振动监测数据处理方法研究

振动作为桥梁健康监测关键参数之一,是评价桥梁整体安全性能的重要指标。目前在国内外关于桥梁振动监测的研究工作中,研究的重点常常是振动数据的采集、存储、分析、应用,忽略对振动数据的预先处理,这明显是不符合实际工作需求的。该文阐述桥梁振动监测数据的特点,指出振动监测数据需预先处理的必要性,对常用的数据处理方法进行详细列举,并逐一介绍每种方法的特点。

掺MgO混凝土结构微膨胀发展历程的监测方法

基于埋入式振弦应变计的工作原理,提出了一种掺MgO混凝土结构膨胀历程的监测方法,将该方法实施于某隧道侧墙混凝土结构案例中,对比不同约束监测点对应变数据的影响,以及掺与不掺MgO对现浇混凝土实体结构收缩性能的影响,并通过差值分析使掺MgO现浇混凝土结构膨胀历程得到了实现。

炼化离心泵状态监测与故障诊断技术应用

为提高炼化企业转动设备管理水平,以中国石化炼化企业设备完整性管理体系为依据,落实转动设备预防性工作,要求对于A、B级设备开展以状态监测、实时数据采集系统为基础的监控分析工作。本文主要介绍离心泵振动状态监测和故障诊断技术。通过建立振动状态监测系统,对离心泵实现在线或离线振动数据监测;利用数据采集器,采集机泵运行时的振动信号,通过频谱分析法,诊断离心泵常见故障,准确判断设备的运行状态,提高设备的可靠性,保障其平稳安全运行。

大气颗粒物浓度智能监测方法设计

为实现对大气颗粒物浓度的精准监测,开展颗粒物浓度智能监测方法的设计研究。根据现场大气颗粒物浓度测量需要,选用某公司特制的半导体激光器作为主要光源设备,设计设备技术参数,选择大气颗粒物浓度测量中的光源;构建一个以锥形桶为进入通道的监测环境,基于振动测量理论,设计颗粒物浓度的智能监测。设计对比实验,实验结果证明:设计的智能监测方法在实际应用中的效果良好,该方法可以实现对大气颗粒物浓度的高精度监测。

光纤测振技术在高铁轨下结构病害自动监测中的应用

针对高铁轨下结构层脱空病害,通过数值模拟和现场试验,研究利用光纤测振技术进行实时监测的有效性。选取已发生病害的某段线路,采用基于Φ-OTDR原理的分布式光纤振动监测系统,将测振光纤铺设于2条钢轨的中间的轨道板表面,然后将光纤引出至轨道外监测基站,通过DOVS光纤振动分析仪采集和记录病害修复前后的振动数据,并利用冲击映像法对轨下结构进行详细检测。研究表明,轨下结构脱空病害对振动的影响分为振动激励和振动放大,近振动源可能引发共振,其放大作用相较于远振动源明显,可达原振幅的2~3倍。

基于实时监控的混凝土坝振捣施工质量动态评价研究

混凝土坝仓面振捣质量评价是混凝土坝施工质量控制的重要手段。传统方法采用事中人工经验控制振捣参数与事后有限的钻芯取样点检测相结合来控制混凝土坝振捣施工质量;此外,现有的振捣台车振捣监控研究中仅采用单个测距仪进行测距,且缺乏仓面振捣质量评价方法。针对混凝土坝仓面内振捣施工实时质量动态评价和反馈控制的挑战和难点,本文提出了基于双测距仪联合测距方案的混凝土坝振捣施工质量实时监控方法,并基于该方法建立了考虑混凝土特性参数不确定性的混凝土振捣质量动态评价模型,该模型主要包括以下内容:(1)引入"信息熵"理论对混凝土特性参数的不确定性进行量化分析;(2)在考虑参数不确定性的情况下基于随机森林算法提出了混凝土抗压强度动态计算方法,并将计算结果应用于混凝土坝全仓面振捣质量评价。将该模型与多元线性回归和人工神经网络算法建立的评价模型进行了对比分析,验证了本模型的一致性和优越性。应用本文提出的评价方法对我国某西南碾压混凝土坝工程仓面变态混凝土区域的振捣质量进行了动态评价,结果表明,该方法能够准确评价仓面混凝土振捣质量,为混凝土坝振捣施工质量控制提供了理论依据。

地下工程爆破振动监测与分析

对大冶铁矿尖林山矿体无底柱分段崩落法回采进路采矿爆破振动速度的测试与研究表明 ,质点爆破振动速度与单响最大爆破药量和测点到爆心的距离密切相关 ,符合《爆破安全规程》

基于子空间方法的风机齿轮箱故障预测算法

为了减少风机齿轮箱严重故障的发生,提出了一种基于随机子空间识别方法的齿轮箱故障预测算法。该算法首先建立齿轮箱的随机状态空间模型,并利用正常运行时的振动监测数据计算模型的参数矩阵的特征值,并将其作为参考特征值;然后将由实际振动数据所求得的特征值与参考特征值进行比较,如果两者误差很小,则说明齿轮箱正常,反之则异常。为了减少计算量,引入均方根误差(RMSE)作为齿轮箱故障判别指标,并利用统计过程控制(SPC)原理定义该指标的阈值。最后,对一台实际风机的振动监测数据进行仿真,结果表明了所提出算法的有效性。