Berührungslose Analyse des Sägebandzustands/Contactless saw blade analysis. Investigation of saw blade conditions using the Barkhausen Effect

Im Bereich der Bandsägeprozesse werden Verschleißzusammenhänge meist aus dem Antriebsstrom und einer Bandspannungsüberwachung prognostiziert. In-Prozess-Messungen zur Identifizierung von Rissen oder Eigenspannungsänderungen finden hier bisher nur unzureichend Anwendung. Für eine prozessbegleitende Zustandsüberwachung bei Sägebändern wird in der vorgestellten Versuchsreihe der Einsatz eines Messsystems zur Aufzeichnung des Barkhausen-Rauschens geprüft und es werden erste Signalzusammenhänge dargestellt.   In the field of band sawing processes, wear relationships are usually predicted from the drive current and band tension monitoring systems. In-process measurements for the identification of cracks or residual stress changes have only been used insufficiently so far. In order to implement an online condition monitoring of saw bands, the use of a measuring system recording the Barkhausen noise is tested in the scope of a test series and first signal correlations are presented.

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Use of Time-Dependent Multispectral Representation of Magnetic Barkhausen Noise Signals for the Needs of Non-Destructive Evaluation of Steel Materials

Sensors ◽

10.3390/s19061443 ◽

2019 ◽

Vol 19 (6) ◽

pp. 1443 ◽

Cited By ~ 8

Author(s):

Michal Maciusowicz ◽

Grzegorz Psuj

Keyword(s):

Extraction Procedure ◽

Measuring System ◽

Barkhausen Noise ◽

Magnetic Barkhausen Noise ◽

Barkhausen Effect ◽

Destructive Testing ◽

Time Frequency ◽

Use Of Time ◽

Definition Of ◽

Non Destructive

Due to the existing relationship between microstructural properties and magnetic ones of the ferromagnetic materials, the application potential of the magnetic Barkhausen noise (BN) method to non-destructive testing is constantly growing. However, the stochastic nature of the Barkhausen effect requires the use of advanced signal processing methods. Recently, the need to apply time-frequency (TF) transformations to the processing of BN signals arose. However, various TF methods have been used in the majority of cases for qualitative signal conditioning and no extensive analysis of TF-based information has been conducted so far. Therefore, in this paper, the wide analysis of BN TF representation was carried out. Considering the properties of TF transformations, the Short-Time Fourier Transform (STFT) was used. A procedure for definition of the envelopes of the TF characteristic was proposed. To verify the quality of extracted features, an analysis was performed on the basis of BN signals acquired during stress loading experiments of steel elements. First, the preliminary experiments were processed for various parameters of the measuring system and calculation procedures. The feature extraction procedure was performed for different modes of TF representations. Finally, the distributions of TF features over the loading stages are presented and their information content was validated using commonly used features derived from time T and frequency F domains.

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Influence of microstructure on retained austenite and residual stress changes under rolling contact fatigue in mixed lubrication conditions

Wear ◽

10.1016/j.wear.2018.04.002 ◽

2018 ◽

Vol 406-407 ◽

pp. 84-91 ◽

Cited By ~ 13

Author(s):

Mohanchand Paladugu ◽

R. Scott Hyde

Keyword(s):

Residual Stress ◽

Retained Austenite ◽

Rolling Contact Fatigue ◽

Contact Fatigue ◽

Mixed Lubrication ◽

Rolling Contact ◽

Stress Changes ◽

Lubrication Conditions

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Using condition monitoring systems to improve the reliability of overhead electrified railway operations

10.1049/ic:19980981 ◽

1998 ◽

Cited By ~ 1

Author(s):

P. Keen

Keyword(s):

Condition Monitoring ◽

Monitoring Systems ◽

Railway Operations ◽

Condition Monitoring Systems ◽

Electrified Railway

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Analysis of Thermal Stresses and Residual Stress Changes in Railroad Wheels Caused by Severe Drag Braking

Journal of Engineering for Industry ◽

10.1115/1.3439136 ◽

1977 ◽

Vol 99 (1) ◽

pp. 18-23 ◽

Cited By ~ 13

Author(s):

M. R. Johnson ◽

R. E. Welch ◽

K. S. Yeung

Keyword(s):

Residual Stress ◽

Stress Field ◽

Yield Point ◽

Thermal Stresses ◽

Material Behavior ◽

Nonlinear Material ◽

Residual Stress Field ◽

Thermal Stress Field ◽

Stress Changes ◽

Railroad Wheels

A finite-element computer program, which takes into consideration nonlinear material behavior after the yield point has been exceeded, has been used to analyze the thermal stresses in railroad freight car wheels subjected to severe drag brake heating. The analysis has been used with typical wheel material properties and wheel configurations to determine the thermal stress field and the extent of regions in the wheel where the yield point is exceeded. The resulting changes in the residual stress field after the wheel has cooled to ambient temperature have also been calculated. It is shown that severe drag braking can lead to the development of residual circumferential tensile stresses in the rim and radial compressive stresses in the plate near both the hub and rim fillets.

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