A Frequency-Domain Quantitative Diagnosis Method of Centrifugal Compressor Impeller Cracks in Running State

Abstract

The invention discloses a method for quantitative diagnosis of frequency domain of a centrifugal compressor impeller crack. First, structure random mistuning factors caused by reasons like manufacturing error and scale are considered, and the statistical regularity of frequency index under detuning condition is studied, so as to obtain the quantitative relationship between frequency index with crack depth and the level of detuning, present a resonant frequency deviation based quantitative diagnostic indexes for frequency domain of the centrifugal compressor impeller crack, and further establish a database of impeller crack diagnosis. Secondly, the method acquires several front orders of sensitive resonant frequencies of the impeller crack through the vibration signals of the centrifugal compressor rotor, calculates the deviation index of resonant frequency, compares the measured indexes with the established crack diagnosis database, so as to obtain the crack depth and realize quantitative diagnosis of impeller crack. The invention discloses the influence rule of crack on centrifugal compressor unit frequency response characteristics, and provides an effective method for quantitative diagnosis of the impeller crack in the running state.

Description

technical field [0001] The invention belongs to the field of fault diagnosis of mechanical equipment, and in particular relates to a frequency-domain quantitative diagnosis method for impeller cracks of a centrifugal compressor in an operating state. Background technique [0002] Centrifugal compressors are important equipment in national industrial production and are widely used in petrochemical, steel and electric power fields. It is of great significance to ensure their safe and reliable operation for industrial production. Since the impeller is subjected to complex alternating stresses in actual operation, fatigue cracks are initiated in the weak link of the impeller due to high-cycle fatigue damage. Blade fracture accidents will not only cause huge economic losses, but also threaten the lives of personnel on site. In view of the serious consequences of blade fracture accidents, a technology that can reliably diagnose impeller cracks is urgently needed in industrial pro...

AI Technical Summary

Problems solved by technology

[0004] The diagnosis of centrifugal compressor impeller cracks is a recognized diagnostic problem. Currently, there are very few reports on the diagnosis of centrifugal impeller cracks, and there is no set of feasible and reliable impeller crack diagnosis methods.

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