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Introduction
Condition-based maintenance
Condition-based maintenance (CBM) is a widely accepted concept in industry. The idea is simple: keep
plant machinery in good working condition by locating and repairing minor faults before they grow
large enough to cause expensive breakdowns and production stops.
The challenge is to assess machine condition and detect a slow deterioration long before a piece of
equipment grinds to a shuddering halt. In the past, a skilled operator could do this largely without the
help of instruments, by listening, touching, and smelling. Modern machinery is often unattended, sound-
proofed, or out of easy reach. It rotates faster and is less massively constructed, which means that even
a minor deterioration of its working condition can have very serious consequences. Therefore, personal
skill and subjective judgment have to be supported by monitoring systems and instrument readings.
Vibration monitoring
Vibration monitoring is a very useful method for overall assessment of machine condition. Changes in
the vibration level always imply changes in the operating condition. Excessive vibration basically has
three potential causes: something is loose, misaligned, or out of balance. These three causes cover
virtually all possible mechanical faults.
Moreover, the assessment of machine vibration has been much simplified by international standards
which define the acceptable vibration level for a given type of machine and recommend monitoring
methods suitable for industrial purposes.
Effective condition-based maintenance requires economical and simple monitoring methods which can
be applied by maintenance personnel without special training. Their primary task is to locate trouble
spots early and direct the efforts of the maintenance crews to the right place at the right time. Fault
analysis and repairs are a secondary step which may require expert knowledge and a different type of
instrumentation.
VibChecker is designed as a maintenance aid. In accordance with the international standards, it measures
vibration severity over the frequency range 10 to 1000 Hz. It allows a practical classification of machine
condition in relative terms: good, acceptable, just tolerable, or bad. Regular measurements will also
show the development trend of the vibration level and thus the urgency of the maintenance problem:
stable condition, slow deterioration or fast deterioration.
Summary of Contents for VibChecker
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