2020 №04 (01) DOI of Article
2020 №04 (03)

Technical Diagnostics and Non-Destructive Testing 2020 #04
Technical Diagnostics and Non-Destructive Testing #4, 2020, pp. 8-16

Devices for detection of defects at early stages of their initiation at determination of technical condition of mechanisms

R.M. Yuzefovych, I.M. Yavorskyi, I.Y. Matsko, O.V. Lychak, G.R. Trokym, O.Yu. Dzeryn, I.H. Stetsko
G.V. Karpenko Physico-Mechanical Institute of NASU. 5 Naukova str., 79060, Lviv, Ukraine. E-mail: roman.yuzefovych@gmail.com

Vibration signal is the carrier of information about certain system defects, it has the properties of repeatability and stochasticity. These properties allow describing and studying the mathematical model in the form of periodically correlated random process (PCRP). PCRP probabilistic characteristics reflect the modulation interaction of the stochastic and deterministic components of vibration, which arises in the case of defect appearance. Mutual PCRP-analysis of vibration signals, the use of the introduced coherence functions allows detecting defects, classifying their types, as well as determining their location. The combination of multi-point selection of vibration signals, methods of mutual statistical PCVP-analysis and digital signal processing software in the developed compact device for non-destructive testing «Compact-Vibro» allows increasing the efficiency of vibration diagnostics of rotating units of technological facilities during operation without changing their standard operating modes. The monitoring of TPP turbounits by the developed methods allowed revealing a number of typical defects of support slide bearings, which was confirmed during the repair of rotating units. 20 Ref., 17 Tables.
Keywords: nondestructive testing, vibration, periodically correlated random process, specialized devices, defect, slide bearing

Received: 23.10.2020


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