Eccentricity in Steam Turbine

The most common cause of eccentricity is improper operation of the turning gear. Some manufacturers have instrumentation to monitor the condition, corrective action is to run the unit on gear until the unit runs true, others have a scheme of X minutes on gear for x minutes stopped.

Four hours on the gear is usually adequate to straighten a heat bent rotor, unless of course the rotor has developed a permanent bow. If this is the case machining will be required to establish new centers.