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NOTE: After aligning of the machine, tighten the screws coupling the flange
and the flywheel housing first. Then tighten the screws for the coupling
discs and the flywheel across.
Alignment of the generator without coupling discs
The alignment is done in accordance with the recommendations given by the
coupling manufacturer. Parallel, angular and axial alignment of the machine is
required. Some standard publications give recommendations for coupling
alignment, see for example
BS 3170:1972 Flexible couplings for power
transmission
.
In accordance with common practice, parallel and angular misalignment should
not exceed 0.05-0.10 mm and axial misalignment should not exceed 0.10 mm, see
Figure 3-4. Definition of misalignment
. The corresponding run-out is 0.10-0.20
mm for parallel and angular misalignment, and 0.20 for axial misalignment.
Figure 3-4. Definition of misalignment.
Notation used in
Figure 3-2
.
Definition of misalignment
:
•
Parallel misalignment
r.
•
Angular misalignment
b.
•
Axial misalignment
a.
Final alignment
To avoid the force created by misalignment for the machine, correct alignments as
below:
1. Mount the alignment equipment. If gauges are used, it is practical to adjust the
dial gauge in such a way that approximately half of the scale is available in either
direction. Check the rigidity of the gauge brackets in order to eliminate the
possibility of sag, see
Figure 3-5. Alignment check with gauges.
