Machinery Lubrication July August 2008

VIEWPOINT
When It Comes to CBM,
Inspect Success
MARK BARNES
Most companies have discovered to some degree the benefits
of condition based maintenance (CBM). By
definition, CBM entails performing maintenance tasks, not on a
scheduled interval basis (such as operating hours, miles, cycles,
etc.) but rather based on data gathered from certain predictive
maintenance tasks such as oil analysis, vibration analysis, thermography
or ultrasonics. The key benefit to a condition-based
maintenance strategy is that maintenance tasks get done only
when required, based on data, optimizing the utilization of
increasingly scarce maintenance resources. Done properly, there
is little doubt that CBM can and does work.
Routine Inspections
While CBM has proved successful for many companies, all
too often they miss the most basic and often the most effective
form of predictive data gathering: routine operator-based
inspections. While some companies struggle, other companies
have jumped in with both feet, anxious to follow the success
of Toyota and others that have successfully deployed
autonomous maintenance in support of lean manufacturing
initiatives. In fact, as many as 43 percent of all U.S.-based
manufacturers are actively pursuing lean maintenance initiatives
with varying degrees of success.
Just like conventional maintenance practices, autonomous
maintenance is predicated on predictive maintenance and, in
particular, routine inspections. These routine inspections are
usually part of regular operator rounds that are performed each
week, day or shift. But even those companies that are having
success with operator-assisted maintenance sometimes miss the
mark; and while their desires are well-intentioned, their execution
of inspections routes is lacking.
From my experience, the main reasons for this are a lack of
detail and engineering design up front in defining what needs
to be inspected, how it should be inspected and documenting
the required inspection routes. Inspections routes
need to be specific. It’s not sufficient to simply state a task
such as “check pump”. For some, check pump may mean to
feel the housing for temperature. Others may look for signs of
a packing leak, while others may simply check yes, indicating
the pump is indeed still in the same place it was yesterday!
Making the List
The best inspection lists include clear, concise, taskspecific
details for each asset. For lubrication, this includes
details such as: check shaft seals for signs of oil leakage and
check oil level gauge for correct operating oil level. Basic
predictive maintenance data should also be collected. This
might include the differential pressure gauge reading across
the filters, the color and clarity of the oil in the sight glass or
the color of the desiccant in the breather.
6 July - August 2008 machinerylubrication.com Machinery Lubrication