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.

Research on the Correlation Between Oil Menitoring and Vibration Monitoring in Information Collecting and Processing Monitoring

Oil monitoring and vibration monitoring are two principal techniques for mechanical fault diagnosis and condition monitoring at present. They monitor the mechanical condition by different approaches, nevertheless, oil and vibration monitoring are related in information collecting and processing. In the same mechanical system, the information obtained from the same information source can be described with the same expression form. The expressions are constituted of a structure matrix, a relative matrix and a system matrix. For oil and vibration monitoring, the information source is correlation and the collection is independent and complementary. And oil monitoring and vibration monitoring have the same process method when they yield their information. This research has provided a reasonable and useful approach to combine oil monitoring and vibration monitoring.

Sensor Layout of Hoisting Machinery Vibration Monitoring Based on Harmony Genetic Search Algorithm

With the construction of automated docks,health monitoring technology as a parallel safety assurance technology for unmanned hoisting machinery has become a hot spot in the development of the industry.Hoisting machinery has a huge structure and numerous welded joints.The complexity and nonlinearity of the welded structure itself makes the structural failure parts random and difficult to arrange for monitoring sensors.In order to solve the problem of effectiveness and stability of the sensor arrangement method for monitoring the structure of hoisting machinery.Using the global and local search capabilities enhanced by the complementary search mechanism,a structural vibration monitoring sensor placement algorithm based on the harmony genetic algorithm is proposed.Firstly,the model is established for modal analysis to obtain the displacement matrix of each mode.Secondly,the optimal parameter combination is established through parameter comparison,and the random search mechanism is used to quickly search in the modal matrix to obtain the preliminary solution,and then the preliminary solution is genetically summed The mutation operation obtains the optimized solution,and the optimal solution is retained through repeated iterations to realize the decision of the vibration sensor layout of the crane structure monitoring.Combining the comparison test of harmony genetic algorithm,harmony search algorithm and genet-ic algorithm,the fitness of harmony genetic algorithm in X,Y and Z directions were 0.0045,0.0084 and 0.0058,respectively,which were all optimal.And the average probability of deviating from the optimal path is 1.10%,19.34%,and 54.43%,which are also optimal.Harmony genetic algorithm has the advantages of simplicity,fastness and strong global search ability,and can obtain better fitness value and better search stability.

ZIZ-2 Vibration monitoring and diagnosing system for turbine generator units

ZJZ-2 system has the following functions: (1) Real-time on-line sampling and FFT analysis (32 channel); (2) Data aquisition, analysis and storage during start-up and shut-down; (3) Alarming, emergency recognition and fault retrieval; (4) Data aquisition, analysis and storage during daily operation; (5) Recall of historic data; (6) Output of routine reports and tables; (7) Analysis of vibration behaviour: Bode plot, polar plot, spectrum, cascade, waveform, shaft orbit, trend, etc;

Vibration Monitoring and Diagnosis of Pipe-line Pumps on Offshore Platforms

This paper presents the applications of vibration monitoring and a diagnosis technique on the predictive maintenance of pipe line pumps on offshore platforms. The monitored ten pumps are distributed on the past three petroleum platforms of the CACT (C: China offshove Southern; A: Agip; C: Chivron; T: Texaco) Operation Group in the Huizhou oil field. By the periodical vibration survey in recent three years, the typical faults and the vibration features of these pumps have been summarized, which set up the basis for efficient predictive maintenance of this key equipment offshore.

Michelson laser interferometer-based vibration noise contribution measurement method for cold atom interferometry gravimeter

The measurement performance of the atom interferometry absolute gravimeter is strongly affected by the ground vibration noise.We propose a vibration noise evaluation scheme using a Michelson laser interferometer constructed by the intrinsic Raman laser of the atomic gravimeter.Theoretical analysis shows that the vibration phase measurement accuracy is better than 4 mrad,which corresponds to about 10-^10 g accuracy for a single shot gravity measurement.Compared with the commercial seismometer or accelerometer,this method is a simple,low cost,direct,and fully synchronized measurement of the vibration phase which should benefit the development of the atomic gravimeter.On the other side,limited by equivalence principle,the result of the laser interferometer is not absolute but relative vibration measurement.Triangular cap method could be used to evaluation the noise contribution of vibration,which is a different method from others and should benefit the development of the atomic gravimeter.

Diesel Engine Fault Diagnosis with Vibration Signal

When the vibration of diesel engine structure is measured, the signal is composed of a very complex superposition of the contributions of different vibratory sources modified by their respective transmission paths. These sources originate from several internal phenomenon in the engine such as combustion pressure variation, unbalanced reciprocating and rotating parts. In a diesel engine, movement parts work in a specific order. Once the starting point is determined, occurrence of work order in different cycle phases can be determined. This could successfully use to identifying of impulses in complex vibration signal of a diesel engine. From the variation of features of those impulses, it is possible to determine the working condition of the engine. This can use to fault diagnosis of diesel engine, specially faults related to combustion process.

Application of ″Black Box″ to fault diagnosis of rotating machine

Presents the successful application of an accident recalling system in the Linyuan refine oil works as part of a rotating machine vibration state monitoring and fault diagnosis system which consists of vibration pre processor,comparator and plus generator, and system gives the CPU of vibration state monitoring and fault diagnose system an interrupt plus when the vibration amplitude exceed a dangerous level to enable it to sample and store the vibration data and gets the accident data timely because the interval between the happening of accident and the beginning of sampling are shorter than 1 ms.

Analysis of blasting damage in adjacent mining excavations

Following a small-scale wedge failure at Yukon Zinc＇s Wolverine Mine in Yukon, Canada, a vibration monitoring program was added to the existing rockbolt pull testing regime. The failure in the 1150 drift occurred after numerous successive blasts in an adjacent tunnel had loosened friction bolts passing through an unmapped fault. Analysis of blasting vibration revealed that support integrity is not compromised unless there is a geological structure to act as a failure plane. The peak particle velocity（PPV） rarely exceeded 250 mm/s with a frequency larger than 50 Hz. As expected, blasting more competent rock resulted in higher PPVs. In such cases, reducing the round length from 3.5 m to 2.0 m was an effective means of limiting potential rock mass and support damage.

Study on Rolling Mill Gear Box and Design of Multichannel Fault Diagnosis

Gear box places an important role rolling mill.Its reliability decides the machine operation.Due to the important role,if the key machine is broken because of gear box′s malfunction,the whole production devices will be influeued.Therefore,it′s very important to monitor the gear box online.Good monitoring system can help companies to better process fault diagnosis.The design sets up a monitoring system with Enwatch polled mode on-line acquisition module and Odyssey software.By calculating the data,the problem of the monitoring system is find,the plans to collect signal is made,the problems of monitoring gear box′s multichannel vibration are solved and the malfunctions initially are estimated according to the signal,which has theoretical basis and practical meanings.

Electromechanical coupling properties of a self-powered vibration sensing device for near-surface observation tower monitoring

The wind-induced vibration of a remote sensing tower is the key factor affecting the stability of image sensing and structural reliability. Monitoring the vibration of a long-time unattended tower is critical to its proper operation. Currently, most monitoring devices are supplied with wired power or battery, significantly limiting their practical applications in remote areas. In this paper,a self-powered vibration sensing device based on hybrid electromechanical conversion mechanisms is proposed. The device depends on a cylindrical magnetic levitation structure sensitive to ambient vibration for transferring mechanical energy and is taken as a dual-functional heterogeneous integrated system comprising electromagnetic, piezoelectric, and triboelectric generators. When the device vibrates under environmental force driving, the suspension magnet reciprocates vertically and generates induced electromagnetic energy, which is used to power the device. Moreover, the triboelectric and piezoelectric voltages,respectively originating from magnet impact on two separation friction materials and magnetic field repulsion-induced strain deformation of a piezoelectric sheet, are used as the synergistic sensing signals. To improve the output energy, a set of dualsegmented annular coils is designed in an electromagnetic generator, which greatly avoids the obstructive effect of the suspended magnet on the magnetic flux change at its end. Compared with a whole isochoric coil, it increases the output voltage by 78.3%.For the triboelectric sensing module, a silicone film with a large specific surface area is fabricated via 3D modification, which improves the output voltage by 29.4%. Furthermore, a pair of piezoelectric sensing modules is set to improve the accuracy of comparative sensing data. The experimental measurement shows that the device maintains a high sensitivity of 6.711 V(m s;);and excellent linearity of 0.991 in the range of 0–14 m s;. This work provides a practical strategy for the vibration monitoring of remote sensing towers and exhibits attractive potential in early warning and data analysis.

Hybrid fiber Bragg grating sensor for vibration and temperature monitoring of a train bearing

We report a fiber Bragg grating（FBG）-based sensor for the simultaneous measurement of a train bearing’s vibration and temperature. A pre-stretched optical fiber with an FBG and a mass is designed for axial vibration sensing. Another multiplexed FBG is embedded in a selected copper-based alloy with a high thermal expansion to detect temperature. Experiments show that the sensor possesses a high resonant frequency of 970 Hz, an acceleration sensitivity of 27.28 pm/g, and a high temperature sensitivity of 35.165 pm/℃. A resonant excitation test is also carried out that demonstrates the robustness and reliability of the sensor.

Optical Fiber Grating Vibration Sensor for Vibration Monitoring of Hydraulic Pump

In view of the existing electrical vibration monitoring traditional hydraulic pump vibration sensor, the high false alarm rate is susceptible to electromagnetic interference and is not easy to achieve long-term reliable monitoring, based on the design of a beam of the uniform strength structure of the fiber Bragg grating （FBG） vibration sensor. In this paper, based on the analysis of the vibration theory of the equal strength beam, the principle of FBG vibration tuning based on the equal intensity beam is derived. According to the practical application of the project, the structural dimensions of the equal strength beam are determined, and the optimization design of the vibrator is carried out. The finite element analysis of the sensor is carried out by ANSYS, and the first order resonant frequency is 94.739 Hz. The vibration test of the sensor is carried out by using the vibration frequency of 35 Hz and the vibration source of 50 Hz. The time domain and frequency domain analysis results of test data show that the sensor has good dynamic response characteristics, which can realize the accurate monitoring of the vibration frequency and meet the special requirements of vibration monitoring of hydraulic pump under specific environment.

Design of Vibration Sensor Based on Fiber Bragg Grating

Fiber grating is a kind of new type of fiber optic light source device which has been rapidly changing in the refractive index of the core in recent years. Especially, it can realize the high precision of the external parameters by means of the special structure design and the encapsulation technology [1, 2]. In this paper, a fiber grating vibration sensor which is suitable for vibration monitoring in key areas is designed based on the technical background of vibration monitoring system. The sensor uses a single beam structure and pastes the fiber Bragg grating （FBG） to measure the vibration wavelength on the surface. When the vibration is simply harmonic vibration, the Bragg reflection wavelength will change periodically, and the periodic variation of the wavelength curve can be measured by the fiber grating demodulator, then the correctness of the experimental results is verified. In this paper, through the analysis of the data measured by the demodulator, the MATLAB software is used to verify the data, and the different frequency domains, the modes, and the phase frequency curves are obtained. The measurement range is 0Hz-100Hz, and the natural frequency is 90.6Hz.