The Experts below are selected from a list of 159 Experts worldwide ranked by ideXlab platform

Shi Wengang - One of the best experts on this subject based on the ideXlab platform.

  • rough set theory based approach for fault diagnosis of valves in Reciprocating Pumps
    China Mechanical Engineering, 2002
    Co-Authors: Shi Wengang
    Abstract:

    This paper presents a rough set theory based approach for fault diagnosis of valves in Reciprocating Pumps. This approach can directly extract diagnosis rules for valves from the vibration signals having been processed by the wavelet packet transform. These rules are used to construct rule-based fault diagnosis system for the valves. The system can not only diagnose single fault valve but also identify multiple fault valves. The results of diagnosis show the effectiveness of this approach. The feasibility of this approach also indicates its potential applications on the fault diagnosis of other complex machines.

  • support vector machines based approach for fault diagnosis of valves in Reciprocating Pumps
    Journal of Mechanical Strength, 2002
    Co-Authors: Shi Wengang
    Abstract:

    A Support Vector Machines-based approach is presented for fault diagnosis of valves in Reciprocating Pumps. According to the approach, the input vectors of Support Vector Machines consisted of wavelet packet transform coefficients extracted from the collected vibration signals of valves as the time-frequency characteristics. And these vectors were inputted into a multi-class classifier composed of many Support Vector Machines to identify multiple fault modes of valves. The experimental diagnosis results show that, the approach can not only correctly diagnose single faulty valve but also precisely identify multiple faulty valves. Furthermore, comparing with the traditional artificial neural networks, the approach is more efficient, robust and adaptive, which indicates the potential of the SVMs techniques in machinery fault diagnosis.

  • Application of rough set theory to fault diagnosis of check valves in Reciprocating Pumps
    Canadian Conference on Electrical and Computer Engineering 2001. Conference Proceedings (Cat. No.01TH8555), 2001
    Co-Authors: Shi Wengang, Wang Rixin, Huang Wenhu
    Abstract:

    This paper investigates the application of rough set theory (RST) to fault diagnosis of check valves in three cylinder Reciprocating Pumps. Currently the faults are detected by the operator through readings of flowmeters and piezometers on the output pipeline. However the condition of each valve can not be detected in this way. Therefore a method of vibration measurements is used. A simulation pump is used to generate measurement data for several kinds of faults. To obtain the fault characteristics of the valves, the wavelet packet transform (WPT) is introduced as a preprocessing means of extracting time-frequency information from vibration signals. Furthermore, in order to determine the position of the faulty valve, RST is used in the process of fault diagnosis. It is proved that severe leakage and fault positions can be identified and diagnosed by the above method.

Liu Shulin - One of the best experts on this subject based on the ideXlab platform.

  • ISSPA - Application of improved EMD algorithm for the fault diagnosis of Reciprocating pump valves with spring failure
    2007 9th International Symposium on Signal Processing and Its Applications, 2007
    Co-Authors: Liu Shulin, Zhao Haifeng
    Abstract:

    This paper presents an improved EMD algorithm for the fault diagnosis of Reciprocating pump valves with spring failure. The vibration signal of Reciprocating Pumps is of typical nonstationarity. Although the EMD algorithm adopting the cubic spline interpolation is an effective tool processing non-stationary signal, it couldnpsilat accurately extract fault characteristics from the highly nonstationary signals. So the paper presents a new improved EMD algorithm which adopts Piecewise Cubic Hermite Interpolating Polynomial (PCHIP) as envelope of extrema. Through the simulation and application, it can be shown that the PCHIP can extract fault characteristic of valves more exactly than the spline.

  • Application of improved EMD algorithm for the fault diagnosis of Reciprocating pump valves with spring failure
    2007 9th International Symposium on Signal Processing and Its Applications, 2007
    Co-Authors: Liu Shulin, Zhao Haifeng
    Abstract:

    This paper presents an improved EMD algorithm for the fault diagnosis of Reciprocating pump valves with spring failure. The vibration signal of Reciprocating Pumps is of typical nonstationarity. Although the EMD algorithm adopting the cubic spline interpolation is an effective tool processing non-stationary signal, it couldnpsilat accurately extract fault characteristics from the highly nonstationary signals. So the paper presents a new improved EMD algorithm which adopts Piecewise Cubic Hermite Interpolating Polynomial (PCHIP) as envelope of extrema. Through the simulation and application, it can be shown that the PCHIP can extract fault characteristic of valves more exactly than the spline.

  • fault diagnosis approach based on binding energy model for valves of Reciprocating Pumps
    Journal of the Harbin Institute of Technology, 2005
    Co-Authors: Liu Shulin
    Abstract:

    Combining the singular value decomposition of matrix a new approach of fault diagnosis for the valves of three-cylinder Reciprocating Pumps is investigated based on the binding energy model of the recognizing process between antigens and antibodies in natural immune systems. The result of fault diagnosis for pump valves in three-cylinder Reciprocating pump shows the methods proposed is of tolerance and robust. In addition , the new fault diagnosis approach is visible and explainable.

  • immune system based approach for on line fault diagnosis of Reciprocating Pumps
    China Mechanical Engineering, 2002
    Co-Authors: Liu Shulin
    Abstract:

    The main task of an immune system is to detect and eliminate the non-self materials called antigens such as virus and cancer cells which come from inside and outside of the living system.A negative-selection algorithm proposed is able to detect any change,which is inspired by the negative-selection mechanism of an immune system. In this paper, the algorithm is improved to make it suitable for the fault diagnosis of a mechanical equipment. Moreover, based on the improved algorithm a new method of fault diagnosis of Reciprocating Pumps is proposed and its feasibility is proved by on-line fault diagnosis of Reciprocating Pumps successfully. In addition, the method of the novel fault diagnosis can also be applied to other fields.

Zhao Haifeng - One of the best experts on this subject based on the ideXlab platform.

  • ISSPA - Application of improved EMD algorithm for the fault diagnosis of Reciprocating pump valves with spring failure
    2007 9th International Symposium on Signal Processing and Its Applications, 2007
    Co-Authors: Liu Shulin, Zhao Haifeng
    Abstract:

    This paper presents an improved EMD algorithm for the fault diagnosis of Reciprocating pump valves with spring failure. The vibration signal of Reciprocating Pumps is of typical nonstationarity. Although the EMD algorithm adopting the cubic spline interpolation is an effective tool processing non-stationary signal, it couldnpsilat accurately extract fault characteristics from the highly nonstationary signals. So the paper presents a new improved EMD algorithm which adopts Piecewise Cubic Hermite Interpolating Polynomial (PCHIP) as envelope of extrema. Through the simulation and application, it can be shown that the PCHIP can extract fault characteristic of valves more exactly than the spline.

  • Application of improved EMD algorithm for the fault diagnosis of Reciprocating pump valves with spring failure
    2007 9th International Symposium on Signal Processing and Its Applications, 2007
    Co-Authors: Liu Shulin, Zhao Haifeng
    Abstract:

    This paper presents an improved EMD algorithm for the fault diagnosis of Reciprocating pump valves with spring failure. The vibration signal of Reciprocating Pumps is of typical nonstationarity. Although the EMD algorithm adopting the cubic spline interpolation is an effective tool processing non-stationary signal, it couldnpsilat accurately extract fault characteristics from the highly nonstationary signals. So the paper presents a new improved EMD algorithm which adopts Piecewise Cubic Hermite Interpolating Polynomial (PCHIP) as envelope of extrema. Through the simulation and application, it can be shown that the PCHIP can extract fault characteristic of valves more exactly than the spline.

Eberhard Schlucker - One of the best experts on this subject based on the ideXlab platform.

  • detection of cavitation phenomena in Reciprocating Pumps using a high speed camera
    Chemical Engineering & Technology, 2010
    Co-Authors: Karsten Opitz, Eberhard Schlucker
    Abstract:

    Cavitation in Reciprocating positive displacement Pumps is still an insufficiently understood problem. For a better understanding of the effects of cavitation in Reciprocating positive displacement Pumps, high-speed camera measurements were done under real operating conditions. In this work, emphasis is put on the recording of cavitation phenomena for further investigations. Exemplarily, the occurring cavitation phenomena for different valve designs are described on the basis of high-speed sequences for selected cavitation conditions and the results are discussed.

T D Short - One of the best experts on this subject based on the ideXlab platform.

  • induced flow Reciprocating Pumps part 2
    Proceedings of the Institution of Mechanical Engineers Part A: Journal of Power and Energy, 1999
    Co-Authors: J D Burton, T D Short
    Abstract:

    AbstractThe application of the induced flow principle is particularly important for modern high-speed Reciprocating diaphragm Pumps. Subresonant systems have been available commercially for more than two decades now. After reviewing such systems, the paper evaluates the much more recent development of over-resonant running. A dynamic model is presented together with the electrical analogue, and the paper indicates that over-resonant induced flow Pumps seem particularly suited to electrically driven solar (photovoltaic)- and wind-powered applications.

  • induced flow Reciprocating Pumps part 1
    Proceedings of the Institution of Mechanical Engineers Part A: Journal of Power and Energy, 1999
    Co-Authors: J D Burton, T D Short
    Abstract:

    AbstractA water column, contained in a rigid pipe equipped with a foot valve, may be set in oscillation and bounced against a hydraulic spring at the lower end. In this way, water may be lifted inertially. The use of such induced flow pumping stretches back to at least the eighteenth century. After exploring these roots the paper proceeds to illustrate modern applications, mainly for hand-and wind-operated water-lifting systems in remote areas. Two arrangements for maintaining the water column in oscillation are examined. By analysis and experiment it is shown that greatly improved performance is achieved by permitting the water column to rebound freely.