| The management of equipment condition
monitoring results involves the following:
1. Assure that there is a strategy for identifying
critical equipment which cannot be allowed to fail in
service.
2. Assure that critical, functional locations are
monitored adequately to detect possible degradation and
pending failures.
3. Set a monitoring schedule for each piece of equipment
based on its criticality and failure rate.
4. Assure that equipment is monitored as required and if
it is not measured during routine inspections, that it
is assessed on a special task to prevent missing its
required interval.
5. Assure that all condition problems are easily visible
to managers and maintenance staff.
6. Track the time period that a condition problem has
bee open to prevent equipment problems from being
overlooked.
7. Track work orders assigned to each machine condition
problem and know when that work order is closed. Once
the work order has been closed, validate the quality and
results of the maintenance work with a condition survey
of applicable technologies.
Extending Installed Life (MTBF)
As condition problems are found and equipment is
repaired, it is critical to identify the most probable
root case or causes of failure. Typical root causes of
failure include;
• Over/Under Greasing
• Contaminated Lubricant
• Dirty Cooling Passages
• Overload
• Power Quality
• Imbalance
• Over/Under Tightening
• Abrasive Wear
• Lightening Strike
• Internal Moisture
• Excessive Starts
• Loss of Lubrication
• Misalignment
• Inappropriate Design
• Process Contamination
• High Ambient Temperature
Once the plant analyzes hundreds of failures by
equipment type and plant location, patterns of root
cause of failures are likely to emerge. For all critical
equipment, the equipment should receive a precision
installation, validation of an acceptable baseline and a
countermeasures plan to offset the top equipment type
and location of root causes of failure. When this
reliability management strategy is put into place,
careful tracking of both equipment and location MTBF is
needed to identify poor reliability equipment or
locations.
Another method of tracking a plant’s reliability
maturity is to tabulate the number of assets with faults
each month. Typically a plant just starting predictive
monitoring will see about 10% of assets monitored with
degradation. As a program of prescribed maintenance is
implemented and equipment faults are fixed prior to
failure, the failure rate declines to about 5% of total
monitored assts. With the elimination of top root causes
of failure, the failure rate declines to about 2.5% of
total assets.
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