Abstract: A method for performing a resonance test on a multicomponent component wherein fast and simple classification of the state of the component is ensured by carrying out the resonance test in an automated manner on blade assemblies, in which frequency images of new and used components are compared with each other. For performing a resonance test by direct mechanical excitation of a multicomponent component in the initial state, relevant acoustic parameters of the airborne sound are determined or are numerically computed and deposited in a database. The method includes performing an excitation of a component after use in order to produce structure-borne vibrations in the component and the airborne sound resulting therefrom, measuring the airborne sound by a spaced-apart microphone, determining the relevant acoustic parameters, wherein this is compared with the initial state, and deviations are detected.

Abstract: A fast and simple classification of the state of the component is ensured by carrying out the resonance test in an automated manner on blade assemblies, in which frequency images of new and used components are compared with each other.

Abstract: A method for operating a machine plant having a shaft train, including: a) determining the harmonic frequency of a torsional vibration mode of the shaft train and determining mechanical stresses arising during a vibration period of the torsional vibration mode; b) determining a correlation for each torsional vibration mode between a first stress amplitude, at a position of the shaft train that carries risk of stress damage, and a second stress amplitude, at a measurement location of the shaft train, using stresses determined for the respective torsional vibration mode; c) establishing a maximum first stress amplitude for the position; d) establishing a maximum second stress amplitude, corresponding to the maximum first stress amplitude, for the measurement location; e) measuring the stress of the shaft train while rotating; f) determining a stress amplitude at each harmonic frequency; g) emitting a signal when the stress amplitude reaches the maximum second stress amplitude.

Abstract: A method for operating a machine plant having a shaft train, including: a) determining the harmonic frequency of a torsional vibration mode of the shaft train and determining mechanical stresses arising during a vibration period of the torsional vibration mode; b) determining a correlation for each torsional vibration mode between a first stress amplitude, at a position of the shaft train that carries risk of stress damage, and a second stress amplitude, at a measurement location of the shaft train, using stresses determined for the respective torsional vibration mode; c) establishing a maximum first stress amplitude for the position; d) establishing a maximum second stress amplitude, corresponding to the maximum first stress amplitude, for the measurement location; e) measuring the stress of the shaft train while rotating; f) determining a stress amplitude at each harmonic frequency; g) emitting a signal when the stress amplitude reaches the maximum second stress amplitude.

Abstract: A turbomachine having a rotor is provided, wherein the rotor comprises a central holding element and rotor elements which are arranged thereon, is intended to permit faster start-up without reducing the lifetime of the rotor, while permitting better predictions relating to the remaining lifetime of the rotor. To this end, a contact element is arranged in a region of the rotor between the holding element and the rotor element, wherein the contact element comprises a temperature measurement device.