Volume no :3, Issue no: 1, -2 January and April (2011)

INFLUENCE OF LOAD AND INTERFERENCE IN VIBRATION-BASED DIAGNOSTICS OF ROTATING MACHINES

Author's: Tomasz Galka
Pages: [1] - [19]
Received Date: February 01, 2011
Submitted by:

Abstract

The paper deals with the influence of machine load and interference on symptom values in rotating machinery diagnostics. In a typical industrial plant environment, this influence often results in very irregular symptom time histories. A theoretical treatment, based on suitable models, is presented and briefly discussed. Cursory analysis of available data shows that, in general, influence of load and interference cannot be neglected. It is therefore important to obtain some knowledge of its relative magnitude, as it directly affects diagnostic reasoning.

The paper presents some results obtained with available databases for large utility steam turbines. Irrespective of turbine type, these data reveal considerable qualitative similarity. On their basis, it may be concluded that in the harmonic frequency range influences of load and interference may often be considered negligible. Observed symptom time histories are thus determined mainly by machine condition evolution. In the blade frequency range, these influences are much stronger and produce considerable fluctuations. They have to be taken into account in order to arrive at a correct machine condition estimation.

Keywords

diagnostic symptom, rotating machinery, technical condition.