Hi every one

We have a GE frame 5 Gas Turbine MS5001P coupled to Generator through reduction gear. Recently during shutdown high axial movement observed on generator rotor. Reduction gear is double helical. Pinion is coupled to turbine through gear type load coupling. Bull Gear shaft is hollow and a quill shaft is inserted in it. Generator Rotor is coupled to bull gear using quill shaft. Quill shaft has integral flange at generator end which is bolted to generator rotor flange. At the other end quill shaft has splines on outer dia and a hub with splines at inner dia is installed on quill shaft. This hub is bolted to gear. As per GE manual Hub is installed with positive interference on quill shaft. There is no thrust bearing for pinion, bull gear and generator

Load Gear was manufactured by GE Lynn. Type is S-634

As per my understanding generator rotor along with quill shaft should be able to slide inside hollow bull gear shaft in order to allow generator rotor to attain its magnetic center in operation.

Please advise if some one has experience of disassembly of load gear quill coupling on MS 5001P units.

 

This type of gear box are very old version and no more in production.

The axial movement is due to excess of electromagnetic force which normal practice, but it become more if the grounding of the electro-mechanical force is not released due to oil leaks and spillages on carbon bruches. which should be checked frequently.

What are the clearances of bearings 5, 6, 7 and 9?
How is the gen. pedestal bearing (no 9)?
How is the oil drains and oil tank vacuum?
How is the oil distributor inside the gear box?

good luck

<b>Moderator's Note:</b> I think "bruches" should be "brushes."