Abstract: In a method for monitoring plants with mechanical components, measured values (xiT; xiu) are determined at predeterminable time intervals for a fixed set of parameters (xi). The measured values (xiT) which are determined for various working points during a modelling phase are used for the generation of a model for the operating behavior of the components. With the help of the model for the operating behavior at least one monitoring value (r; snu) is derived at predeterminable time intervals which is independent of the respective current working point. The temporal behavior of the monitoring value (r; snu) is used for estimating the wear in the components and/or for the detection of operating disturbances.

Abstract: In a method for monitoring the condition of a mechanical seal in an apparatus provided with a rotating part, in particular in a pump which has a rotating shaft for the forwarding of a fluid, the sound emission of the seal is continually measured at discrete times in the operating state of the apparatus and at least one statistical characteristic value is won from the acoustic signals. The analog acoustic signals are converted prior to the determination of the statistical characteristic value into analog demodulated signals, the maximum frequency of which is less than about 50 kHz.