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Frequency response analysis is increasing become a popular technique for assessment of the mechanical integrity of Shunt reactor. This method can diagnose whether a fault exists in core and windings. This paper introduces the test principle and process of frequency response analysis. The vibration device was installed on the shunt reactor. The diagnosis in accordance with the actual fault. The results indicate that frequency response analysis method is feasible. [ABSTRACT FROM AUTHOR]

Economic progress observed in recent years triggered the need for the expansion of transportation infrastructure as well as the growing interest in the land located in close proximity to already existing buildings. Erecting new buildings within compact housing imposes on the investors the obligation to create a particular amount of parking places. The expansion of road and motorway network requires developing the areas with complex geology, whose use was previously economically unjustified. The above mentioned aspects cause the need for technologies that make it possible to take maximum advantage of small free city spaces or to found engineering structures almost in any possible geo-hydrological conditions. Most of the available soil improvement techniques are accompanied with noise and vibrations. When the amplitudes of vibrations go beyond the levels defined as safe in the code of practice, or when the vibrations become exceedingly perceptible by the humans, it is however possible to correct the technology of the works' execution. This work presents selected aspects of the active designing, using the investigation of the impact of vibrations that occur during the soil improvement and piling works, on adjacent engineering structures. [ABSTRACT FROM AUTHOR]

Measurement techniques are developing to enable the monitoring of the vibrations transferred to the surroundings in course of geotechnical works, thus making it possible to carry out those works in a safer manner. A separate problem is posed when dealing with historic buildings, which may potentially come within the impact of vibrations. Intensive construction works carried out in the neighborhood of not infrequently old and valuable structures may threaten the historic housing, hence their safety aspect should be thoroughly considered. That concern for the existing buildings of historical value stimulated the development also of the new research area, namely the impact of deep foundations on the structure of the existing buildings. Inappropriate selection of technology for particular development conditions may lead to such problems as cracking of the adjacent structures or their settlement for unknown reasons. That negative impact can be reduced or even avoided when the vibration is investigated before (in order to get the picture of the so called "environment background") and at the time when the construction works are initiated. Then, in carrying out construction works, the range of permissible vibration velocities and frequencies should be taken into account. As the old proverb says, necessity is the mother of invention; and so, on the market appeared a lot of firms offering a wide array of geotechnical technologies. The research conducted at the Faculty of Civil Engineering at Wroclaw University of Technology aim at defining the influence of ongoing works on the surroundings, as well as at preparing the guidelines on the selection and/or calibration of the technology. The experience gained so far is sufficient to offer services for companies. Those services are supposed to both: help with the calibration of the technology, as well as to protect the contractors from unjustified claims from the neighbors of the construction site. At the same time, the stored database of the surveys may, after being systematized, play a significant role in the non-destructive diagnostic testing of buildings. [ABSTRACT FROM AUTHOR]

The real-time monitoring of events in an industrial plant is vital, to monitor the actual conditions of operation of the machinery responsible for the manufacturing process. A predictive maintenance program includes condition monitoring of the rotating machinery, to anticipate possible conditions of failure. To increase the operational reliability it is thus necessary an efficient tool to analyze and monitor the equipments, in real-time, and enabling the detection of e.g. incipient faults in bearings. To fulfill these requirements some innovations have become frequent, namely the inclusion of vibration sensors or stator current sensors. These innovations enable the development of new design methodologies that take into account the ease of future modifications, upgrades, and replacement of the monitored machine, as well as expansion of the monitoring system. This paper presents the development, implementation and testing of an instrument for vibration monitoring, as a possible solution to embed in industrial environment. The digital control system is based on an FPGA, and its configuration with an open hardware design tool is described. Special focus is given to the area of fault detection in rolling bearings. [ABSTRACT FROM PUBLISHER]

The paper proposes a Rough-set Theory based methodology for multi-class fault diagnosis of induction motors using Hilbert Transform (HT). Depending on the motor condition the vibration signals are associated with unique predominant frequency components and instantaneous amplitudes. The axial vibration signals acquired through data acquisition system are split into different mono-components using Kaiser windowed FIR band pass filter. Statistical features of the Hilbert coefficients obtained from the mono-component signals are used as attributes for fault classification. Rough-set theory is successfully applied for dimensionality reduction of the attributes (by 67%) with almost no degradation of classification accuracy. The proposed Rough-set-Hilbert model eliminates the limitation of wavelet based fault diagnosis technique. The computational efficiency of the proposed classifiers increase due to selection of most relevant features, even at a low sampling frequency of 5120 Hz. [ABSTRACT FROM PUBLISHER]

Vehicle-to-infrastructure communication applications are more and more common in automotive and off-highway vehicle testing. To perform online wireless vibration monitoring of off-highway vehicles, high-end wireless accelerometers are required that combine a high data rate with a low communication latency. However, such high-end wireless sensors are not easy to find in the market. To address this market need, we have developed a prototype of a high-end wireless vibration sensor node. Our sensor node consists of a digital accelerometer, a Field Programmable Gate Array (FPGA) that acts as the central processing and control unit, and a short-range ultra-wide band (UWB) radio. The sensor node was validated in our lab by performing throughput and latency measurements. As a result we have demonstrated that our high-end wireless sensor node achieves a high throughput of 180Mbps and a low latency of 1ms, while still offering the flexibility to be adapted to different applications. [ABSTRACT FROM PUBLISHER]

Since vibration and shock loads are always known as a destructive loads while drilling a borehole and reason for tool failure, more detailed studies of vibration and dynamic behavior of drill string and bottom hole assembly to prevent any time lost and hole problem is needed to be done. To achieve these objectives, monitoring the vibration in laboratory scale is performed. This paper describes a research in which drilling process and related vibration are monitored. A fully capable small drilling rig (CDC miniRig) and vibration sensor sub are used to measure them in different ranges of weight on bit and rotary speed of drill string. Dynamic stability window based on experimental test results to have minimum vibration is also suggested. [ABSTRACT FROM PUBLISHER]

Describes the vibration problem of the existence of intelligent prosthetics on the market, In order to monitor the vibration source, Using ANSYS modal analysis on smart prosthetics, Will be effective to estimate the vibration characteristics of the overall structure, And set up a vibration test platform to monitor the vibration signal, This paper presents a set of intelligent artificial limb vibration measurement and analysis methods, and has been the main source of vibration and noise of intelligent prosthetic work. [ABSTRACT FROM PUBLISHER]

In this study, a motor condition diagnostic was achieved through the implementation of an Artificial Neural Network (ANN), successfully applying into a predictive maintenance system. Electrical motors were monitored to obtain data to train the ANN. Out of these monitoring, vibration signatures were used as the input layer, and the motor condition was used as the expert training information. The main objective was to apply neural networks to a condition based predictive maintenance in order to detect the type of system's failure. As a result, the expert system can be utilized to decrease the possible failures in operating system and increase the availability and effectiveness of a system. [ABSTRACT FROM PUBLISHER]

The specifics of high-performance centrifugal pumps operation are analyzed. According to the accumulated vibration monitoring data the reasons of vibration increase are analyzed and the factors which effect this increasing. The correlation analysis is applied to prior detection of pump fault. [ABSTRACT FROM AUTHOR]

The vibration monitoring of rotating machinery is widely used while observing the state of machinery or aggregates. On the base of monitoring results, diagnostic procedures are performed and responsible decisions are made, so measurement uncertainty impacts safe exploitation of the equipment and the whole object. The purpose of this paper is to provide some results of the investigations made in this field. The analysis showed that periodic and permanent vibration monitoring system: can be characterized by different features, thus the uncertainty model is changing — in permanent monitoring systems the statistical component vanish, but in periodic systems this component plays a main role. Also the uncertainty models were suggested. They allow during the design and maintenance of the vibration monitoring and diagnostics predict or determine through the real data measurement uncertainty and the change of false decision probability. The ratio of the mean am uncertainty is used as a parameter which describes the impact of the uncertainty to a decision making in diagnostic procedures. [ABSTRACT FROM AUTHOR]

This report allows to overview advantages of using condition monitoring especially in initial period of new enterprise exploitation. Modern means and methods of measuring and analysis today enable to determine faults, reasons of their appearance and means to remove faults. The condition monitoring implementation in an enterprise can be chosen by the way when this service is arranged from external supplier. A centralized rotating machines vibration monitoring system is presented. [ABSTRACT FROM AUTHOR]