Teco Installation and Maintenance Manual
TEFC Squirrel Cage Induction Motors
Teco Electric and Machinery Company
Manual Number: IOM ~ TEFC Rev.01
12
3.6.4 It is desirable, in normal operation that the motor operates, so that no axial
force is exerted on the coupling.
The motor shaft and the driven shaft should be aligned within the following
tolerances in both angular and parallel alignment (refer Table 1).
Units in mm
TIR
Total
Indicated
Runout
Solid
Coupling
Flexible
coupling
Dimension C
Medium, Low speed up to 2500
RPM
0.04
0.05
High speed over 2500 RPM
0.03
0.03
Dimension A
Medium, Low speed up to 2500
RPM
0.03
0.04
High speed over 2500 RPM
0.03
0.03
Table 1
3.6.5 Angular misalignment is the amount by which the centre lines of the driver
and driven shaft are skewed. It can be measured using a dial indicator set
up as shown in fig 4. The couplings are rotated together through 360
degrees so that the indicator does not measure runout of the coupling hub
face. The shaft should be forced against either the in or out extreme of
their end float while being rotated.
Fig. 4
Fig. 5
3.6.6 Parallel misalignment is the amount by which the centre lines of the driver
and the driven shafts are out of parallel. It can be measured using the dial
indicator as shown in fig. 5. Again the couplings are rotated together
through 360 degrees so that the indicator does not measure runout of the
coupling hub outside diameter.
