R
EVERSE
D
IAL
I
NDICTOR
M
ETHOD
:
The reverse dial method is similar to the laser alignment method, however, less
accurate and can take more time. This method also takes shaft-to-shaft readings but
uses two dial indicators instead of a laser for measurement. As both shafts are rotated
together, both the parallel and angular misalignment are combined in one indicator
reading. This method will require the use of two special brackets to hold the indicators
during the measurements.
S
INGLE
D
IAL
I
NDICATOR OR
R
IM AND
F
ACE
A
LIGNMENT
M
ETHOD
:
This method is similar to the rough alignment but more accurate since dial indicators
are used. The rim reading measures the offset between the coupling halves. The face
reading measures the angular difference between the faces of the coupling.
The procedure is as follows -
1) Clamp dial indicator on driving (Motor) side of coupling and locate the indicator
probe on the rim (O.D.) of the driven (Blower) coupling half. Rotate shaft and take
reading at 90-degree intervals to determine the amount of parallel misalignment.
Misalignment of coupling is ½ of Total Indicator Reading (TIR).
2) Locate indicator probe at the extreme point on the coupling face, rotate shaft and
take readings at 180-degree intervals to correct any angular misalignment.
3) Once the angular misalignment has been corrected be sure to re-check the rim
alignment to ensure it is still correct.
REV 06/23/23
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