Turbine Baseplate

[planck121]

Hello,
During our construction/grouting of a single stage turbine and gearbox, the baseplate was incorrectly grouted leading to issues now with acheving alignment of the turbine gear train. There are a few proposals floating around - one would be to regrout the entire baseplate, the other would be to actually modify the already grouted baseplate but cutting and rewelding supports. Are there any issues with the latter approach, I have typically seen regrouting as an alternative but given the schedule constraints there are proposals on cutting and modifying the basepate insitu.

Thoughts would certainly help.

Thanks

 

[jayrod12]

Are we talking about levelling grout, or was the baseplate embedded in a grout pocket?

 

[SlideRuleEra]

Are there any issues with the latter approach (modify existing work)...

Vibration is a major source of turbine problems. Taking short cuts such as cutting, rewelding, etc. can easily introduce minute misalignment that will cause trouble for the life of the machine.

Do it right, regrout the entire baseplate.

http://www.SlideRuleEra.net

http://www.VacuumTubeEra.net

 

[Tmoose]

"there are proposals on cutting and modifying the baseplate insitu. "
Got pictures and drawings? Some baseplates and machine bases are for ALL practical purposes un-fillable in my opinion.

Is the problem relative positioning of separate base plates?

Is the problem insufficient "filling" of the space under the base plate ? Resulting in base plate flexibility and inconsistent effect of shims placed under the machine feet?

Cementitious or epoxy grout? What is the grout make and model?

What were the ambient conditions during grout placement and curing?
How long was the grout allowed to cure before placing the equipment?

Was this the millwrights' first experience with this type of machinery, or this type of grout?
Was a representative of the grout manufacturer or the turbine mfr on hand for the base plate work?
Is there confirmation the underside of the baseplate was prepared correctly? (Often the requirement is sand blasted to near-white metal surface cleanliness in accordance with something like SSPC-SP6 or ISO8501-1:2007 Sa2 . )


If the problem is some relatively small areas of incomplete filling, epoxy grout injection can be a decent solution.