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VIBXPERT Balancing 11.2010
Preparatory activities
The preparations include the mounting of the measurement compo-
nents.
The machine must be disconnected before carrying out any work
on the machine and it must be protected against being switched on
again inadvertently!
Assembly
1. Try to find out the cause of the imbalance visually and fix it if
possible. Example: Remove any coatings from the impeller, fasten
any loose balancing weights or tighten any loose screws on the
foundation.
If the machine cannot be balanced in-situ, it must be firmly
mounted on a rigid foundation (directly on frames or on vibration
isolators).
2. Determine the measurement and balancing planes (see figure on
next page). Mount the vibration transducer on the bearing
housing at the measurement location with the highest vibration
values. Note that:
• The measurement plane should be in the middle of the bearing
and close to the balancing plane and the plane of the center of
gravity (e.g. impeller side, rotor).
• Vibrations are transferred via the outer ring of a bearing in a
radial direction. Thus, mount the transducer on the side
(horizontal) or on the top of the bearing (vertical). Find
suitable measurement locations by searching for positions with
the highest vibration values using a hand-held probe.
• The transducer should be attached as close as possible to the
bearing. Prevent signal attenuation due to excessively long
transmission paths or bearing covers or similar. The direction
of measurement must correspond to the main direction of
vibration (mostly horizontal). If the measurement direction is
horizontal, mount the transducer on the lower half of the
bearing housing.
• Wherever possible, use transducers which are screwed onto the
machine or attach the transducer using a magnetic adapter
(VIB 3.420). The transducer should not be attached to compo-
nents with intrinsic vibrations, e.g. covers.
• Hand-held probes are not suitable for balancing!
• Only for balancing in two planes: Determine the second plane
(B) in the same way.
TIP: Plane B should be on the rigid drive side near to the
coupling and plane A on the soft output side away from the
coupling (see figure on next page).
Balancing: Preparations
WARNING!
Note
Содержание VIBXPERT Balancing
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