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1

Bearing fault detection using a method involving absolute value spectrum and impulsivity evaluation

Bouaouiche Karim, Menasria Yamina, Khalifa Dalila

Diagnostyka

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2024

|

Vol. 25, No. 2

art. no. 2024213

EN

This study analyzes vibration signals related to bearing defects using a method that reconstructs an effective signal. This reconstruction is based on the determination of the instantaneous amplitude and phase. Then, a decomposition method is applied to the amplitude and phase to obtain several simple functions. Once the functions are obtained, an evaluation of impulsivity is performed on each function using the proposed parameter. This selects functions that contain fault data. The important signal is then identified and used. After the creation of the effective signal, filtering by a morphological operator with a structuring element is applied to improve the signal quality. Finally, in the spectrum of the absolute values of this signal, the defect can be detected from the frequency of the peaks. Signals from different databases were analyzed using the proposed method, illustrating the results in the form of high-amplitude peaks in the frequency of bearing component defects.

2

Przebudowa mostu w Krzyżowicach z uwagi na znaczne górnicze osiadania terenu

Bętkowski Piotr

Przegląd Budowlany

|

2023

|

R. 94, nr 7-8

75--79

PL

W artykule opisano historię techniczną mostu w Krzyżowicach. Obiekt intensywnie osiadał, ale brak było istotnych przemieszczeń na łożyskach. Górnicze osiadanie terenu spowodowało znaczne zmniejszenie światła pionowego, tj. obniżenie mostu względem zwierciadła rzeki, konieczna była przebudowa mostu. Po przebudowie mostu wydłużono ściany górnicze poza obiekt, w krótkim czasie doszło do znacznych zmian w położeniu przyczółków. W artykule opisano starą konstrukcję mostu, nową konstrukcję mostu, podano wyniki długoletnich obserwacji i pomiarów oraz wskazano, jak należy projektować zabezpieczenia na wpływy górnicze w przypadku nietypowych wymuszeń górniczych.

EN

Article describes the technical history of a bridge in Krzyżowice. The object settled intensively, but there were no significant displacements on the bridge bearings. Mining subsidence caused a significant reduction in vertical light, i.e. lowering the bridge in relation to the river level, it was necessary to rebuild this bridge. After the reconstruction of the bridge, mining walls were extended beyond the object, in a short time there were significant changes in the position of the abutments. The article describes old bridge construction, new bridge construction, gives the results of long-term observations and measurements, and indicates how to design protection against mining influences in the case of unusual mining impacts.

3

Fault diagnosis of bearings based on SSWT, bayes optimisation and CNN

Yan Guohua, Hu Yihuai, Shi Qingguo

Polish Maritime Research

|

2023

|

nr 3

132--141

EN

Bearings are important components of rotating machinery and transmission systems, and are often damaged by wear, overload and shocks. Due to the low resolution of traditional time-frequency analysis for the diagnosis of bearing faults, a synchrosqueezed wavelet transform (SSWT) is proposed to improve the resolution. An improved convolutional neural network fault diagnosis model is proposed in this paper, and a Bayesian optimisation method is applied to automatically adjust the structure and hyperparameters of the model to improve the accuracy of bearing fault diagnosis. Experimental results from the accelerated life testing of bearings show that the proposed method is able to accurately identify various types of bearing fault and the different status of these faults under complex running conditions, while achieving very good generalisation ability.

4

Operating characteristics of bearings with magnetic nanoparticles doped lubricant

Krenicky Tibor, Mascenik Jozef, Coranic Tomas, Ruzbarsky Juraj

Mining Machines

|

2023

|

vol. 41, iss. 3

168--174

EN

The main aim of the presented research was to investigate theoperational characteristics of a bearing when alternative lubricants were used for comparison with a standard lubricant, including that containing magnetic nanoparticles. The bearing was subjected to varying operating conditions, differing in terms of mechanical load status. The monitoring of the bearing operation parameters primarily focused on monitoring the velocity and acceleration of vibrations, as well as the operating temperature of the bearing. Thebearingwith lubricant doped by magnetic nanoparticles exhibited reduced vibration velocity and acceleration values both under no load conditions and when subjected to a mechanicalload. The operating temperature slightly increased during testing in the case ofthe bearing with nanoparticles compared to the bearing using the original lubricant.

5

Detection of defects in a bearing by analysis of vibration signals

Bouaouiche Karim, Menasria Yamima, Khalifa Dalila

Diagnostyka

|

2023

|

Vol. 24, No. 2

art. no. 2023203

EN

This work presents the analysis of vibration signals by an approach consists of several mathematical tools more elaborate such as the Hilbert transform, kurtogram, which allows the detection of vibration defects in a simple and accurate way. The steps or methods inserted in the process one complementary to the other as scalar indicators generally used in monitoring to follow the evolution of the functioning of a machine when an abnormal functioning it must make a diagnosis to detect the failing element through the use of a process. The determination of the defective organs at an optimal time is a very important operation in the industrial maintenance, which keeps the equipment in a good condition and ensures the assiduity of work. To see the effectiveness of fault detection by the proposed approach by analyzing the real vibration signals of a bearing type 6025-SKF available on the Case Western Reserve University platform.

6

Detection and diagnosis of bearing defects using vibration signal processing

Bouaouiche Karim, Menasria Yamina, Khalfa Dalila

Archive of Mechanical Engineering

|

2023

|

LXX, nr 3

433--452

EN

This work presents an analysis of vibration signals for bearing defects using a proposed approach that includes several methods of signal processing. The goal of the approach is to efficiently divide the signal into two distinct components: a meticulously organized segment that contains relatively straightforward information, and an inherently disorganized segment that contains a wealth of intricately complex data. The separation of the two component is achieved by utilizing the weighted entropy index (WEI) and the SVMD algorithm. Information about the defects was extracted from the envelope spectrum of the ordered and disordered parts of the vibration signal. Upon applying the proposed approach to the bearing fault signals available in the Paderborn university database, a high amplitude peak can be observed in the outer ring fault frequency (45.9 Hz). Likewise, for the signals available in XJTU-SY, a peak is observed at the fault frequency (108.6 Hz).

7

A novel, machine learning-based feature extraction method for detecting and localizing bearing component defects

Cherif Bilal Djamal Eddine, Seninete Sara, Defdaf Mabrouk

Metrology and Measurement Systems

|

2022

|

Vol. 29, nr 2

333--346

EN

Vibration analysis for conditional preventive maintenance is an essential tool for the industry. The vibration signals sensored, collected and analyzed can provide information about the state of an induction motor. Appropriate processing of these vibratory signals leads to define a normal or abnormal state of the whole rotating machinery, or in particular, one of its components. The main objective of this paper is to propose a method for automatic monitoring of bearing components condition of an induction motor. The proposed method is based on two approaches with one based on signal processing using the Hilbert spectral envelope and the other approach uses machine learning based on random forests. The Hilbert spectral envelope allows the extraction of frequency characteristics that are considered as new features entering the classifier. The frequencies chosen as features are determined from a proportional variation of their amplitudes with the variation of the load torque and the fault diameter. Furthermore, a random forest-based classifier can validate the effectiveness of extracted frequency characteristics as novel features to deal with bearing fault detection while automatically locating the faulty component with a classification rate of 99.94%. The results obtained with the proposed method have been validated experimentally using a test rig.

8

Application for vibration diagnostics

Stakhova Anzhelika

Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska

|

2022

|

T. 12, nr 3

46--49

EN

This paper considers the issue of developing an application for vibration diagnostics of bearings of functional pairs of critical structures, this application should help in monitoring and diagnosing bearings, using vibration signals, without disassembling the functional unit itself. It is known that vibration diagnostics is effective and there is a tendency to reduce the cost of its implementation. Monitoring and diagnostics based on vibration parameters can be applied at any time, even after several years of equipment operation, when the costs of preventive maintenance and repair will exceed the economically justified value. Also, in the work, the basics of the subject area for the development of mobile applications are considered, and a review of existing solutions is made. Requirements for the application for performing vibration diagnostics are formulated. The architecture is designed and the data description for the application of vibration diagnostics is carried out.

PL

W artykule poruszono problematykę opracowania aplikacji do diagnostyki wibracyjnej łożysk par funkcjonalnych konstrukcji krytycznych, która to aplikacja powinna pomóc w monitorowaniu i diagnozowaniu łożysk z wykorzystaniem sygnałów wibracyjnych, bez demontażu samego zespołu funkcjonalnego. Wiadomo, że diagnostyka wibracyjna jest skuteczna i istnieje tendencja do obniżania kosztów jej wykonania. Monitoring i diagnostyka na podstawie parametrów drgań może być stosowana w dowolnym momencie, nawet po kilku latach eksploatacji urządzeń, gdy koszty obsługi prewencyjnej i napraw przekroczą ekonomicznie uzasadnioną wartość. W pracy rozważane są również podstawy tematyki tworzenia aplikacji mobilnych oraz dokonywany jest przegląd istniejących rozwiązań. Sformułowano wymagania dla aplikacji do wykonywania diagnostyki wibracyjnej. Zaprojektowano architekturę i wykonano opis danych dla aplikacji diagnostyki wibracyjnej.

9

Bearing fault detection and diagnosis based on densely connected convolutional networks

Niyongabo Julius, Zhang Yingjie, Ndikumagenge Jérémie

Acta Mechanica et Automatica

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2022

|

Vol. 16, no. 2

130--135

EN

Rotating machines are widely used in today’s world. As these machines perform the biggest tasks in industries, faults are naturally observed on their components. For most rotating machines such as wind turbine, bearing is one of critical components. To reduce failure rate and increase working life of rotating machinery it is important to detect and diagnose early faults in this most vulner-able part. In the recent past, technologies based on computational intelligence, including machine learning (ML) and deep learning (DL), have been efficiently used for detection and diagnosis of bearing faults. However, DL algorithms are being increasingly favoured day by day because of their advantages of automatically extracting features from training data. Despite this, in DL, adding neural layers reduces the training accuracy and the vanishing gradient problem arises. DL algorithms based on convolutional neural networks (CNN) such as DenseNet have proved to be quite efficient in solving this kind of problem. In this paper, a transfer learning consisting of fine-tuning DenseNet-121 top layers is proposed to make this classifier more robust and efficient. Then, a new intelligent model inspired by DenseNet-121 is designed and used for detecting and diagnosing bearing faults. Continuous wavelet transform is applied to enhance the dataset. Experimental results obtained from analyses employing the Case Western Reserve University (CWRU) bearing dataset show that the proposed model has higher diagnostic performance, with 98% average accuracy and less complexity.

10

Methods for assessing the technical condition of bearing hubs in means of transport

Stanik Zbigniew, Kubik Andrzej, Hadryś Damian, Csiszár Csaba

Zeszyty Naukowe. Transport / Politechnika Śląska

|

2021

|

z. 113

191--204

EN

This article presents two methods of testing bearing hubs, which may supplement the existing subjective and unreliable methods of diagnostics of rolling bearings used in wheel bearing hubs of motor vehicles and other means of road transport. One of the most important elements responsible for the safety of a vehicle is the bearing hub. Regular monitoring of the technical condition of bearings should become an obligation at vehicle inspection stations when carrying out a technical inspection of a vehicle, authorising it to travel on public roads. This article presents the results of vehicle tests with signs of damage to rolling bearings, using two test stands: one on which the dynamic balancer acted as a device for accelerating the wheel, and the other, which was designed as a test dedicated to automotive rolling bearings, where a dynamic weighbridge was used as the wheel drive, made it impossible to test the wheel at lower rotational speeds. The newly designed and manufactured bearing testing device eliminates the disadvantages of the previous stand, and additionally, enables the measurement of a fully loaded bearing hub, which enables the simulation of real operating conditions on the bearing hub.

11

Impact of selected operational parameters on measures of technical condition of rolling bearings in means of transport built based on analysis of vibration signals

Kubik Andrzej, Stanik Zbigniew, Hadryś Damian, Csiszár Csaba

Zeszyty Naukowe. Transport / Politechnika Śląska

|

2021

|

z. 111

89--98

EN

This article presents an innovative method of diagnostics of rolling bearings used in the bearing nodes of motor vehicles, with the use of a prototype specialist stand. The tests were carried out based on a developed research plan, which included the impact of damage to the bearing and tyre of the vehicle, as well as the vehicle speed. Vibration accelerations were recorded in three measurement axes. Signal spectra were created based on the time courses of the vibration signals and were further analysed. The presented method is aimed at detecting excessive wear of rolling bearings in wheels from its early period.

12

Method of Measuring Frictional Resistance In Pendular Motion

Opałka Mariusz

Tribologia

|

2021

|

nr 1

15--19

EN

This paper presents a methodology for conducting tribological sliding tests based on decaying vibrations in pendular motion. The proposed method of determining the (averaged) coefficient of friction in pendular motion is based on measuring the potential kinetic energy. The method is characterized by a short measuring time and enables a quick comparison of the friction coefficients of different materials.

PL

W artykule przedstawiono metodykę prowadzenia badań tribologicznych materiałów ślizgowych na podstawie drgań gasnących w ruchu wahadłowym. Zaproponowana metoda wyznaczania współczynnika tarcia (uśrednionego) w ruchu wahadłowym opiera się na pomiarze energii potencjalno-kinetycznej. Zaproponowana metoda cechuje się krótkim czasem prowadzenia pomiarów oraz umożliwia szybkie porównanie współczynników tarcia dla różnych materiałów.

13

Modeling and analysis of the stress-strain state of robotic systems

Khayrnasov Kamil

Przegląd Elektrotechniczny

|

2021

|

R. 97, nr 8

66--69

EN

The paper considers the methodology for modeling and analyzing the performance of a robotic system: multi-stage semi-natural simulation stand designed to simulate the flight characteristics of guidance systems in ground conditions. The results of the calculation showed that the use of a composite material gives advantages over the traditionally used materials for the manufacture of such stands: magnesium alloys, due to the high specific strength of the composite material.

PL

W artykule rozważono metodykę modelowania i analizy działania systemu robotycznego: wieloetapowe półnaturalne stanowisko symulacyjne przeznaczone do symulacji charakterystyk lotu systemów naprowadzania w warunkach naziemnych. Wyniki obliczeń wykazały, że zastosowanie materiału kompozytowego daje przewagę nad tradycyjnie stosowanymi materiałami do produkcji takich stojaków: stopami magnezu, ze względu na wysoką wytrzymałość właściwą materiału kompozytowego.

14

Aspekty transformacji eksploatacyjnej warstwy wierzchniej bieżni łożysk tocznych : przegląd

Szyca Mikołaj

Developments in Mechanical Engineering

|

2021

|

nr 17(9)

103--110

PL

Zużywanie warstwy wierzchniej bieżni łożysk tocznych jest powszechnym problemem ich eksploatacji. Badania jej zużycia prowadzi się od ponad 50 lat, jednak z uwagi na zastosowanie łożysk tocznych w licznych maszynach przemysłowych oraz rozwój technologii konieczne jest stałe aktualizowanie wiedzy na ten temat. W pracy zaprezentowano przegląd publikacji dotyczących problemów zmęczeniowych i tribologicznych transformacji eksploatacyjnej łożysk tocznych w aspekcie bieżących kierunków rozwoju tej dziedziny.

EN

Wear of the top layer of the raceway of rolling bearings is a common problem in bearing operation. Its wear has been realized for over 50 years, but due to the use of rolling bearings in many industrial machines and technology development, it is necessary to constantly update the knowledge on this subject. The article reviews articles on the fatigue and tribological problems of the exploitation transformation of rolling bearings in terms of the current development trends in this field.

15

Numerical Analysis of the Influence of Temperature on the Friction Resistance of a Metal-Polymer Sliding Pair

Opałka Mariusz, Kowalewski Piotr, Ptak Anita

Tribologia

|

2020

|

nr 4

17--26

EN

The paper presents numerical calculations of polymer sliding bearings during their operation at low temperatures. Calculations of the frictional moment and the contact area were performed for bearing pans made of PA and PEEK. In the numerical model, the influence of temperature on the mechanical properties (modulus of longitudinal elasticity) and tribological properties (coefficient of friction) were taken into account. The diversified influence of the temperature and thickness of the polymer bearing pans was demonstrated with regards to elements made of different polymer materials. At low temperatures (up to T = -50°C), a different (depending on the used polymer) influence of mechanical and tribological properties on the resistance to motion was found. The ABAQUS calculation package and the finite element method (FEM) were used in the calculations

PL

W pracy przedstawiono obliczenia numeryczne polimerowych łożysk ślizgowych podczas pracy w niskiej temperaturze. Obliczenia momentu tarcia oraz powierzchni styku wykonano dla panewek wykonanych z PA i PEEK. W modelu numerycznym uwzględniono wpływ temperatury na własności mechaniczne (moduł sprężystości podłużnej) oraz właściwości tribologiczne (współczynnika tarcia). Wykazano zróżnicowany wpływ temperatury oraz grubości panewki polimerowej dla elementów wykonanych z różnych materiałów polimerowych. W niskiej temperaturze (do T = -50°C) stwierdzono zróżnicowany (w zależności od zastosowanego polimeru) wpływ cech mechanicznych i tribologicznych na opory ruchu. Do obliczeń z zastosowaniem metody elementów skończonych (MES) wykorzystano pakiet ABAQUS do obliczeń.

16

Modelling and Simulation Testing of Main Bearing Loads and Strains in Crankshafts Caused by Deviations in the Position of the Shaft Journal and Bearing Axes

Nozdrzykowski Krzysztof, Grządziel Zenon

Multidisciplinary Aspects of Production Engineering

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2020

|

Vol. 3, Iss. 1

41--56

EN

This article presents the results of a simulation, testing the variation of main bearing loads and strains in crankshafts caused by geometrical deviations of the bearing system to justify the necessity and purposefulness of measurements of both the shape and axes position deviations of crankshaft journals. Measurements of these deviations at the existing level of applied measuring techniques are significantly limited. The research also accentuates the practical implementation of a measuring system equipped with the so-called flexible support system for the measured object, developed at the Maritime University of Szczecin. This system makes it possible to eliminate elastic deformations of the crankshaft due to its own weight, whereby the measurements of geometrical deformations of the crankshafts can be carried out with appropriate accuracy in conditions corresponding to the non-reference measurements when determining the object measured in counterpoints. The obtained results have fully confirmed the purposefulness of the conducted research and the validity of the theses.

17

Control and prediction protocol for bearing failure through spectral power density

Castilla-Gutiérrez Javier, Fortes Juan Carlos, Davila Jose Miguel

Eksploatacja i Niezawodność

|

2020

|

Vol. 22, no. 4

651--657

EN

This paper aims to analyse the results of the comparative study of the characteristic frequencies, in terms of Power Spectral Density (PSD), generated by an SKF6322 bearing in a rotational blower. Among all the analysed frequencies, we have focused on the ones generated by the shaft rotation speed, the one on the blades and the ones of the SKF6322 bearing, such as the tracks, the cage and the balls. For this study, we followed the ISO 10816 criteria, both in the sampling part and in the data analysis, using the speed values in terms of PSD, which improves the results in both high and low frequencies. This study can be used to predict the performance of bearings and their future failure, determining the most decisive frequency, the one with the highest incidence and the relative influence of each one on the different positions and monitoring coordinate axes. This procedure can be applied to improve the predictive maintenance protocol in order to improve the performance, efficiency and reliability of the equipment with bearings in their systems.

18

Underwater Noises of Open-Circuit Scuba Diver

Korenbaum Vladimir, Kostiv Anatoly, Gorovoy Sergey, Dorozhko Veniamin, Shiryaev Anton

Archives of Acoustics

|

2020

|

Vol. 45, No. 2

349--357

EN

The features of respiratory noises and noises of fins for open-circuit scuba divers, indicating a multipole character of noises emission, are specified in cameral conditions. It demonstrates a possibility to detect low-frequency components of noises of fins with pressure gradient sensor in near field. A possibility of estimating the respiratory rate of an open-circuit scuba diver is demonstrated at distances up to 100 m in real sea. It gives an opportunity of estimating the bearing (time delay in a pair of hydrophones) for the open-circuit scuba diver by respiratory noises at distances up to 150 m in real sea. Thus, low-frequency underwater noises of open-circuit scuba divers may be successfully applied to monitor the safety of diving and to prevent waterside intrusion by trespassers.

19

A Comparison of Wear Properties of Water Lubricated NBR and PTFE Sliding Bearings

Piątkowska Ewa

Tribologia

|

2019

|

nr 1

29--35

EN

The excessive wear of a journal shaft can be caused by many factors, for example, working conditions (e.g., temperaturę, slip speed, the type of lubricant), pressure, the type of material used on the bearings and shafts and their roughness, as well as contamination remaining in the system. This paper presents the roughness profiles co-operating with a rubber (NBR) and polytetrafluoroethylene (PTFE) bushes. The conditions of cooperation between the two materials tested in the sliding combination with the stainless steel journal were the same in each pair of bearings (PV); therefore, the comparison of their wear depends only on the material properties of the bush and the deformation of the journal shaft caused by the bending moment. To assess the size of the journal shaft, they were tested using a profilograph. In addition to the journal shaft, bearings were also evaluated, the wear level of which was noticed without the use of specialized equipment.

PL

Nadmierne zużycie czopa wału okrętowego może być spowodowane wieloma czynnikami, np. warunkami pracy (temperatura, prędkość poślizgu, naciski, rodzaj czynnika smarnego), rodzajem materiału zastosowanego na panwie łożysk i czopy wałów oraz ich chropowatością, a także zanieczyszczeniami dostającymi się do układu. W niniejszym artykule przedstawione zostały profile chropowatości czopa wału okrętowego pracującego w panwi wykonanej z gumy (NBR) oraz z politetrafluoroetylenu (PTFE). Warunki współpracy obu badanych materiałów w skojarzeniu ślizgowym z nierdzewnym czopem były jednakowe w każdej parze łożysk (PV), dlatego też porównanie stopnia ich zużycia zależy jedynie od własności materiału panwi oraz deformacji czopa wywołanej momentem zginającym. W celu oceny wielkości zużycia czopów zostały one poddane badaniu za pomocą profilografometru. Poza czopem wału ocenie poddane zostały również panwie łożysk, których stopień zużycia dostrzegalny był bez użycia specjalistycznego sprzętu.

20

Monitorowanie i diagnostyka łożysk w turbinach parowych

Nowicki Ryszard

Przegląd Mechaniczny

|

2019

|

nr 4

28--34

PL

W artykule omówiono współcześnie obowiązujące zasady poprawności instalacji czujników umożliwiające realizację jakościowo możliwie najlepszych pomiarów dla sygnałów pozyskiwanych z tych czujników. W przypadku licznych turbozespołów pracujących w kraju (łącznie z tymi najnowszymi) opisane w artykule zasady są mniej lub bardziej naruszone.