Rotor-stator rub is not very common, but hazardous state, which does not allow normal operation of the machine. The main reasons of rub occurrence are high shaft vibrations, tight clearances of the seals and thermal deformation of stator parts. The diagnostics of rub consists of two tasks. The first task is detection of rub, normally based on tracking of 1X phasor in complex domain or detection of 1X integral submultiples in signal spectrum. The second task is determination of the place, where rub occurred. This paper describes a new method of rub localization based on time-frequency processing of stator vibrations. Developed method uses standardly installed vibration sensors without need of any further equipment. The rub localization method was and tested during experiments on rotor stand and then used in operation of steam turbine. The accuracy of proposed method was verified after an inspection during the steam turbine outage.
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