Page 299 - Subyek Teknik Mesin - Forsthoffers Best Practice Handbook for Rotating Machinery by William E Forsthoffer

Be st Practice 5 .5 Steam Turbine Best Practices

Fig 5.5.5 Rotor natural frequency mode shapes (Courtesy of Elliott Co.)

Fig 5.5.6 Rotor response output at non-drive end bearing (NDE) (Courtesy of Elliott Co.)

change of shaft vibration with speed and the phase angle of un- during every planned start-up and shutdown of every turbo-
balance at any speed. A bode plot is a dynamic or transient sig- compressor. As discussed in this section, the bode plot will pro-
nature of vibration for a rotor system and is unique to that system vide valuable information concerning shaft vibration and phase
for the recorded time frame. Bode plots should be recorded angle at any shaft speed.

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