Turbogenerator Vibration

1. Rotor

2. Casing

The unbalanced part.

The rotor, first. It's the part that moves.

The grub screw in the coupler between the turbo bit and the generator bit. Reasonable cause? - because no-one remembered to balance it. (Your teacher will love it, trust me ).

Dear Mr. Harry,

I want to supplement to the answers given by CR4 Members. In addition to the ROTOR Un-Balance, which is the major source of vibration the following reasons individually or severally vibration will be occuring intensively.

1. In-let and Exhaust Steam Piping, variatios in the Permissible Limits of Forces and the Permissible Bending Moments on the Turbine Flanges, by/from the Steam Pipe Lines.

2. Disturbance in the Spring Supports of the steam pipe line also will create excess vibrations.

3. Coupling Bolts Looseness and or Crack in the Shims.

4. Excessive Bearing clearances

DHAYANANDHAN.S

Hy Harry,

Depends on the situation :

1. If installing a new turbo-generator unit, then presumably the rotor wheel is brand new and balanced to within 4 mm/sec so the source of vibration would be in the alignment between the turbine with the alternator - hence the peak of vibration would be at its coupling.

2. If the unit has been in use for sometime and wear on the turbine rotor wheel is expected, then as correctly stared, the peak would be at the rotor wheel. Wear here is directly related to the steam quality being used. Lower dryness fraction of steam , the greater the possibilities of wear on the rotor blades.