SU1659761A1 - Method of vibration-acoustic diagnostics of mechanisms - Google Patents

Abstract

The invention relates to vibroacoustic diagnostics and can be used to assess the technical condition of vane machines. The purpose of the invention is to increase the reliability of diagnostics by determining the intensity of the main vibroacoustic sources. During operation of the vane machines (compressors, pumps, turbines, etc.), a complex vibration spectrum is excited. The discrete components generated by individual sources are averaged and summed. The continuous components of the spectrum, due to the operation of these same sources, are determined by excluding all discrete components in the informative bands. Determining the intensity of vibration of individual machine components increases the reliability of determining its technical condition. 1 il.

Description

The invention relates to vibroacoustic diagnostics and can be used to assess the technical condition of vane machines.

The purpose of the invention is to increase the reliability of diagnosis by determining the intensity of the main vibro-acoustic sources.

The drawing shows a block diagram of the device that implements the method.

When bladed machines operate (such as compressors, pumps, turbines, etc.), a complex vibration spectrum is excited, consisting of a large number of discrete components, narrowband bursts and continuous spectrum areas. Evaluating the intensity of vibrations due to individual sources (cavitational phenomena, vortex formation, pressure pulsation, friction, etc.) allows the method, which consists in using discrete spectral components using known techniques. The discrete averaged components of the spectrum, excited by any source (gear harmonics, rotor vibrations, blade frequency components, etc.) are summarized in the informative frequency range. The intensity of the discrete components of the vibration of the detected sources is estimated. Then, in the same frequency ranges, the intensity of the averaged components of the continuous spectrum of vibration sources is determined, excluding all discrete components of the spectrum from the result. In order to estimate the intensity of the components of the continuous spectrum, a priori information is used for the attenuation of oscillations in the structure, the location of the electrical measuring device.

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a transducer regarding various sources of vibration, information about the mode of operation, etc. By comparing the total values of the obtained discrete and continuous components of the spectrum of individual sources, it is possible to estimate the intensity of their vibration and determine the technical condition of both the machine as a whole and its individual mechanisms.

A device that implements the method contains serially connected vibro (acoustic) transducers 1 installed on the machine under study (not marked), amplifiers 2 and measuring tape recorder 3. The device also contains a digital analyzer 4 connected to the output of the tape recorder 3, the computing unit 5, connected to the analyzer 4 and the processing unit 6, which, depending on the operation mode, is connected by the command of the unit 5 to the output of the tape recorder 3. The output of the processing unit 6 is connected to the input of the analyzer 4.

The device works as follows.

The signals from transducers 1 are recorded in a multichannel tape recorder 3. From the output of tape recorder 3, the signal of one (or several) channel (catches) is fed to the input of analyzer 4, in which the discrete components of the spectrum of individual vibration sources are allocated in known frequency algorithms in averaged frequency range The sum of the discrete components determines the intensity of the vibration of individual sources. The intensity of the continuous averaged components of the vibration spectrum is determined by

exclude all discrete components in specified frequency bands.

Differential evaluation of discrete and continuous components of the vibration spectrum of individual sources increases the accuracy of determining the technical condition of the machine.

Claims (1)

Vibroacoustic Diagnostic Method mechanisms, which record the vibroacoustic signal at informative points of the mechanism, determine the spectrum of the vibroacoustic signal by spectral analysis, diagnose the mechanism, which in order to increase the reliability of diagnostics by determining the intensity of the main vibroacoustic sources, sampling discrete frequency components spectrum characteristic of certain types of main vibroacoustic sources, determine the level of the continuous spectrum in the range of The frequencies characteristic of other types of main vibroacoustic sources determine the intensity of each main vibroacoustic source by summing the averaged values of discrete frequency components corresponding to each specific vibroacoustic source and adding, excluding discrete components, components of a continuous spectrum in the frequency range corresponding to each a vibroacoustic source of a certain type, and the mechanism is diagnosed by the intensity of each axis. new vibroacoustic source.