GE Energy Motors GEEP-427-I Copyright 2009, The General Electric Company, USA
10
GEEP-427-I Pegasus, Horizontal Induction Motor
TEWAC, Sleeve Bearing
Alignment and Coupling
General
Machines with sleeve bearings are adjusted at
the factory to have approximately 1/2-inch total end play
(4-pole generators have 3/4-inch total end play), with
approximately 1/4-inch end play either way from
magnetic center. The magnetic center and end play limits
are marked on the shaft by a series of three dots. The
rotor will run on magnetic center with approximately
1/4-inch end play in either direction. Sleeve bearings are
not designed to carry any external load thrust.
Accordingly, limited end-float couplings are
recommended for all units with sleeve bearings.
A limited end-float coupling permits relative but
controlled axial movement between the adjacent ends of
two shafts. This movement should be limited (value of
2xC in the table and Fig. 1. below) to be less than the
axial clearance of the AC Machine bearing (value of A +
B in Fig. 1. below), so that the limited, end-float
coupling performs its function. When the correct
alignment is implemented, the coupling prevents the
shaft shoulders on the inboard end of each journal from
exerting thrust on the corresponding bearing. The
recommended clearances in inches for limited, end-float
couplings are given in table 1.
Table 1 Recommended clearances
Fig. 1. Shaft arrangement for limited end-float coupling
Parallel and Angular
Alignment for
Flexible Couplings
SHAFT POSITION
MACHINE END PLAY __A__ __B__ __C__
Shaft ends together
1/2
5/32
11/32
3/32
Shaft ends apart
1/2
11/32
5/32
0
Shaft ends together
3/4
5/16
7/16
3/16
Shaft ends apart
3/4
7/16
5/16
0
Содержание Pegasus MHV GEEP-427-I
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