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Technical data are subject to change without notice.
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Balancing Single - plane Rotors with A2010
Fig. 15
Fig. 16
Fig. 17
The A2010 can be used for simple balancing work
which is accurate enough to reduce machine vibration
to an acceptable level.
The method requires no dismantling of the rotor. It is
suitable for machines with a rotational speed greater
than 600 rpm and with a single-plane rotor, i.e. a rotor
which is considerably larger in diameter than in thick-
ness. Most industrial fans belong to this category.
Prior to balancing it is advisable to clean the rotor and
to repair loose, broken or misaligned components
which also contribute to excessive vibration.
Balancing Method
After measuring the vibration of the rotor bearing, a
trial weight is fastened to the rotor. Three more read-
ings are taken, with the trial weight moved through
120° after each run. Weight and position of the cor-
rection mass are calculated graphically, using the bal-
ancing form on page 77 and a pair of compasses.
First Reading
Measure vibration severity on the rotor bearing in the
radial direction which yields the highest value (usually
horizontal). Use the same measuring point for all fol-
lowing readings, and run the machine at the same
speed. Record the result V
0
of this measurement.
Trial Points
Find and mark three trial points on the rotor where a
weight can be attached. These points must be at an
equal radial distance r from the shaft, and 120° re-
moved from each other. Number the points counter
clockwise 1, 2 and 3.
Trial Weight
The trial weight should be heavy enough to create a
moderate out-of-balance in the rotor (10-30 grams). It
should be screwed or clamped onto the rotor. Its
weight M
t
in grams should be determined before-
hand, as accurately as possible.
Second to Fourth Reading
Attach the trial weight to point 1, run the machine up
to normal speed, measure and record the vibration
severity V
1
. Repeat the measurement with the trial
weight at points 2 and 3, record the results V
2
and V
3
.
Rotor and measuring point
Trial points on the rotor
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