direct coupling alignment
direct coupling alignment
(OP)
Dear Friends
We are going to couple a 1500 HP -4 Pole- sleeve bearing electric motor with one Hellicoidal gear box, is direct coupling, the problem is the process start with in no load for 30 minutes and later take total load so is not a continuos duty.
Wich considerations we have to take account for a good alignment including termal expand and all this? The shaft diameter is 4.5 inches.
Thanks and regards
Carlos
We are going to couple a 1500 HP -4 Pole- sleeve bearing electric motor with one Hellicoidal gear box, is direct coupling, the problem is the process start with in no load for 30 minutes and later take total load so is not a continuos duty.
Wich considerations we have to take account for a good alignment including termal expand and all this? The shaft diameter is 4.5 inches.
Thanks and regards
Carlos





RE: direct coupling alignment
Continuous duty or not has no bearing on the alignment. Type of coupling and gear box may be.
Rafiq Bulsara
http://www.srengineersct.com
RE: direct coupling alignment
Rafiq Bulsara
http://www.srengineersct.com
RE: direct coupling alignment
1 – compromise alignment – midway between target corresponding to no-load temperature and target for continuous run temperuatre.
2 – ignore startup and focus on continuous run conditions.
I am inclined toward #2 because I'm guessing the time spend running at load is a lot longer than the 30 minute no-load.
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(2B)+(2B)' ?
RE: direct coupling alignment
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(2B)+(2B)' ?
RE: direct coupling alignment
How long will it take for the replacements to arrive?
Mike Halloran
Pembroke Pines, FL, USA
RE: direct coupling alignment
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(2B)+(2B)' ?
RE: direct coupling alignment
But it is not common to use belts with sleeve bearings.
On the other hand direct coupled is very common with sleeve bearings.
And a great many of those direct-coupled sleeve bearings machines endure brief periods with less than optimal alignment on the way to thermal equilibrium. It is not ideal, but we have many that operate that way reliably. The question can be a matter of degrees (how misaligned)...none of us can answer that without knowing more.
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(2B)+(2B)' ?
RE: direct coupling alignment
If a proper flexible coupling is used, then there should be no particular concern about alignment changing with warmup, etc.
Mike Halloran
Pembroke Pines, FL, USA
RE: direct coupling alignment
I will attach the analisys later to know your comments.
Regards
Carlos
RE: direct coupling alignment
The vibration analisys is attached all report is wrotte in Spanish but all data was collected with SKF instrument and the keys are the followings:
Figura 4.1 Global vibration levels in NDE Motor
Figura 4.2 Vibration Spectrum NDE Motor
Figura 4.3 Global Vibration levels DE Motor
Figura 4.4 Vibration Spectrum D.E Motor
Figura 4.5 Global Vibration Level in Gearbox
Figura 4.6 Vibration Spectrum in Gearbox
NOTE: Gearbox is double helicall, reducer.
Thanks for the inputs
Carlos
RE: direct coupling alignment
Figura 4.1 Global vibration levels in NDE Motor
Figura 4.2 Vibration Spectrum NDE Motor
Figura 4.3 Global Vibration levels DE Motor
Figura 4.4 Vibration Spectrum D.E Motor
Figura 4.5 Global Vibration Level in Gearbox
Figura 4.6 Vibration Spectrum in Gearbox
NOTE: Gearbox is double helicall, reducer.
Thanks for the inputs
Carlos
RE: direct coupling alignment
Muthu
www.edison.co.in