scholarly journals Railway Vehicle Wheel Flat Detection with Multiple Records Using Spectral Kurtosis Analysis

2021 ◽  
Vol 11 (9) ◽  
pp. 4002
Author(s):  
Araliya Mosleh ◽  
Pedro Aires Montenegro ◽  
Pedro Alves Costa ◽  
Rui Calçada

The gradual deterioration of train wheels can increase the risk of failure and lead to a higher rate of track deterioration, resulting in less reliable railway systems with higher maintenance costs. Early detection of potential wheel damages allows railway infrastructure managers to control railway operators, leading to lower infrastructure maintenance costs. This study focuses on identifying the type of sensors that can be adopted in a wayside monitoring system for wheel flat detection, as well as their optimal position. The study relies on a 3D numerical simulation of the train-track dynamic response to the presence of wheel flats. The shear and acceleration measurement points were defined in order to examine the sensitivity of the layout schemes not only to the type of sensors (strain gauge and accelerometer) but also to the position where they are installed. By considering the shear and accelerations evaluated in 19 positions of the track as inputs, the wheel flat was identified by the envelope spectrum approach using spectral kurtosis analysis. The influence of the type of sensors and their location on the accuracy of the wheel flat detection system is analyzed. Two types of trains were considered, namely the Alfa Pendular passenger vehicle and a freight wagon.

1970 ◽  
Vol 24 (2) ◽  
pp. 99-107
Author(s):  
Gordan Stojić ◽  
Slavko Vesković ◽  
Ilija Tanackov ◽  
Sanjin Milinković

The provision of appropriate quality rail services has an important role in terms of railway infrastructure: quality of infrastructure maintenance, regulation of railway traffic, line capacity, speed, safety, train station organization, the allowable lines load and other infrastructure parameters.The analysis of experiences in transforming the railway systems points to the conclusion that there is no unique solution in terms of choice for institutional rail infrastructure management modes, although more than nineteen years have passed from the beginning of the implementation of the Directive 91/440/EEC. Depending on the approach to the process of restructuring the national railway company, adopted regulations and caution in its implementation, the existence or absence of a clearly defined transport strategy, the willingness to liberalize the transport market, there are several different ways for institutional management of railway infrastructure.A hybrid model for selection of modes of institutional rail infrastructure management was developed based on the theory of artificial intelligence, theory of fuzzy sets and theory of multicriteria optimization.KEY WORDSmanagement, railway infrastructure, organizational structure, hybrid model


2018 ◽  
Vol 2018 ◽  
pp. 1-16 ◽  
Author(s):  
Hua Jiang ◽  
Jianhui Lin

We establish the Injury Model of Wheel Flats with 10 degrees of freedom and calculate the dynamic responses of the railway vehicle system, which include different vehicle speeds and different length flats. The Hilbert envelope spectrum method based on Empirical Mode Decomposition (EMD) is proposed according to the nonstationary characteristics of axle box acceleration (ABA) signal. The vibration characteristics of the ABA are studied thoroughly. And then the effects concerning speed and flat length on the diagnosis results are analyzed. The simulation results show the amplitude corresponding to the frequency component of wheel flats raise with the increasing of the wheel flat length when the single or double wheel flats impact the track at the same vehicle speed. In other words, the longer the wheel flat is, the greater the magnitude of the decomposition result is. In the same vehicle speed, the amplitude corresponding to the frequency component of wheel flat is minimum when the two flats’ phase difference is 180°. With the same flat length (single or double wheel flats), the amplitude corresponding to the frequency components of wheel flats decreases with the increasing of the speed. This method could accurately and effectively identify the frequency of wheel flats.


2020 ◽  
Vol 64 (188) ◽  
pp. 149-160
Author(s):  
Janusz Poliński

Technical diagnostics is an integral part of the railway maintenance process. Through timely maintenance, in addition to ensuring the safety, functional and technical reliability of the infrastructure, maintenance costs are reduced and downtime losses, due to failures or premature repair requests, are eliminated or reduced. The track infrastructure diagnostic tools have evolved. This is related to, among others, the miniaturisation of instruments, reading accuracy during motion, as well as upgraded measurement automation and result analysis. Currently, data obtained from multifunctional diagnostic tools is the basis for the developed Russian railway infrastructure maintenance and operation digital model. The strategic development of mobile diagnostic labs is the gradual transition to solutions with advanced digital analysis, supported by artificial intelligence, monitoring and forecasting. The article presents the development of mobile labs for the railroad infrastructure condition diagnosis up to the current solutions, in which measurements take place without human intervention and the obtained information is transmitted in real time to the analysis and decision centres. Keywords: rail transport, measuring wagons, digitisation of railways, Russian railways


Author(s):  
Grzegorz Liskiewicz ◽  
Kirill Kabalyk ◽  
Andrzej Jaeschke ◽  
Filip Grapow ◽  
Michal Kulak ◽  
...  

Abstract This paper presents tests of an anti-surge system based on pressure derivatives. The control algorithm was proven to work on different machines and with different unstable flow phenomena. Compressors are known to be affected by unstable flow conditions appearing at low mass flow rate conditions. The best known and most dangerous phenomenon is surge, which is a global instability affecting the entire impeller and regions upstream and downstream from it. A list of identified local phenomena includes among others: impeller rotating stall, diffuser rotating stall and inlet recirculation. All have a specific pressure signature that is used for early identification. The method presented in this paper is based on a control parameter named the Rate of Derivative Fluctuation (RDF). This approach involves a simple measure of flow instability that is universal and reacts to flow disturbances. RDF has been already confirmed to identify inlet recirculation and surge. The aim of this study is to conduct real-time tests of an anti-surge system implementing the RDF algorithm triggering the safety valve opening. The study confirmed the optimal position of the monitoring point. The results showed that the RDF is indeed sensitive to different types of flow instabilities appearing in different impellers, and that it provides efficient flow stability monitoring.


2013 ◽  
Vol 13 (12) ◽  
pp. 4808-4816 ◽  
Author(s):  
Massimo Leonardo Filograno ◽  
Pedro Corredera ◽  
Miguel Rodriguez-Plaza ◽  
Alvaro Andres-Alguacil ◽  
Miguel Gonzalez-Herraez

Author(s):  
STEFAN NISKA ◽  
HÅKAN SCHUNNESSON ◽  
UDAY KUMAR

In general railway infrastructure operates in a complex and non homogeneous environment where low power electronics has to function in the similar environment as large voltages and currents from the trains. The environment close to the railway tracks is heavily polluted by electromagnetic (EM) noise from the railway systems itself. The reliability of the railway signalling-, communication-, and control system depends on the degree of isolation from EM noise. It is important to observe the real system and its characteristics in real situation. The complexity of the infrastructure is not easy to simulate or calculate, and therefore measurements were performed on real system in operation. A large number of measurements were made on site at signalling systems and installations of Banverket (the Swedish Rail Administration). By studying and analyzing these measurements, the extent of EMI (Electromagnetic interferences) -related faults can be estimated. In situ measurements must be performed on systems that have obvious problems show increasingly fast and high transients in a DC signalling subsystem. The statistics also show an increased activity of transients during a period before a certain circuit in this system gets out of order. The presented results clearly show how the electromagnets interference effects he signalling system in a signalling box. The measurements in this case study have provided new information on a railway subsystem and have revealed frequencies that are difficult to explain at this moment.


2020 ◽  
Vol 8 (6) ◽  
pp. 2940-2952

Crack detection has always been a dominant requirement for steel industries to ensure quality production and seamless infrastructure maintenance. However, application complexities and defect morphological differences make existing approaches confined. Steel-strip surface often undergoes scratch, crack and fatigue conditions during production. Manual crack detection schemes are no longer effective in current day complex environment. Amongst major steel strip crack detection approaches vision based techniques have found potential; Filamentous crack which is caused due to fatigue or strain is fine-grained and thin and hence highly difficult to be detected by classical morphology and static threshold based schemes. In the present work steel strip surface (filamentous) crack detection system has been developed which employs Varying-Morphological Segmentation (VMS) also called Neuron-Model Segmentation (NMS) in conjunction with local directive filtering and active contour propagation. The proposed method can be stated as an augmented variational framework that employs multi-directional filters for local crack-region identification followed by automated multi-directional region growing and iterative contour evolution which performs level set energy minimization to achieve accurate crack detection even under topological non-linearity and varying illumination conditions Simulation results with standard benchmark data has confirmed that the proposed method exhibits satisfactory performance for steel strip surface cracks


2020 ◽  
Vol 53 (1) ◽  
pp. 115-128 ◽  
Author(s):  
Piotr Gołębiowski ◽  
Jacek Kukulski

In Poland, due to the increase in investments made by railways in recent years, and thus the increase in the replacement value of transport infrastructure, the need for expenditure on infrastructure maintenance will increase in the next 30 years, or the development of the developed transport network will degrade. As part of the overall discipline of resource management, subdiscipline has emerged - infrastructure asset management. As part of the management of railway transport infrastructure, the demand for cheaper maintenance costs will grow. The cost reduction of infrastructure maintenance is possible through meticulous assessment of its condition, rational selection of locations and scope of repairs at the assumed risk level, as well as at the stage of preparation of new construction or modernization projects taking into account aspects of later maintenance. For some time, we have been observing the accumulation of knowledge (methods, programs, procedures) in the country and abroad enabling optimization of infrastructure condition assessment and programming of its maintenance. The implementation of these solutions may result in a more rational use of funds for infrastructure maintenance and not disturb its smooth functioning in operation. The article discusses aspects that should be considered in the design process of railway infrastructure. Particular attention was paid to the durability of steel components of the railway superstructure, maintenance costs as well as aspects related to the capacity of the track node. An example of dependence of selected values of radial arcs depending on their durability and maintenance costs was presented. It was proposed to change the track layout at the Warszawa Srodmiescie passenger stop planned for reconstruction. Calculations of kinematic parameters for various configurations of railway turnouts were performed. Also, calculations of the capacity for the existing track system solution as well as the proposed track system after reconstruction of the analysed Warszawa Srodmiescie railway station were also carried out.


Author(s):  
Zacarias Grande Andrade ◽  
Paola Moraga Contreras ◽  
Enrique Castillo Ron

The paper discusses the advantages and shortcomings of alternate double single track (ADST) lines with respect to double track lines for high speed lines. ADST lines consists of sequences of double and single track segments optimally selected in order to reduce the construction and maintenance costs of railway lines and to optimize the timetables used to satisfy a given demand. The single tracks are selected to coincide with expensive segments (tunnels and viaducts) and the double tracks are chosen to coincide with flat areas and only where they are necessary. At the same time, departure times are adjusted for trains to cross at the cheap double track segments. This alternative can be used for new lines and also for existing conventional lines where some new tracks are to be constructed to reduce travel time (increase speed). The ADST proposal is illustrated with some examples of both types (new lines and where conventional lines exist), including the Palencia-Santander, the Santiago-Valparaíso-Viña del Mar and the Dublin-Belfast lines, where very important reductions (90 %) are obtained, especially where a railway infrastructure already exist.DOI: http://dx.doi.org/10.4995/CIT2016.2016.3426


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