New method of stress and damage diagnosis

Using the roller-bearing diagnosis of machines and equipment as an example, an analysis of diagnosis parameters and functions is presented. This analysis is based on about 700 laboratory and operational experiments and yielded the following results: 1) The original conditions of wearing and tearing components have to be evaluated. 2) Stresses during operation have to be eliminated or taken into account. 3) Diagnosis parameters can be classified according to their correlation with damage. Therefore, root mean square value and peak value of a vibration measurement are inappropriate for diagnosis unless original conditions are taken into account. A new diagnostic parameter K(t) is proposed, which is obtained from r.m.s. and peak value and allows for original conditions of the assembly. The new diagnostic parameter reduces erroneous diagnosis with respect to damage to about 1%