Page 23 - Improving Machinery Reliability

ments, information must be available to identify whether specific or
enterprise-wide solutions must be implemented.

The ability to assemble vital management reports automatically is a
crucial requirement of an information system. An expert should examine
crucial information prior to transmittal and have the opportunity to add
interpretation and editorial comments. However, the expert should not
have to perform manual data gathering. The days when time was avail-
able to compile information from multiple sources and correlate it manu-
ally for management reports is long past. Reports must be self-generat-
ing, or at least all information must be available for report generation.
The traditional method of displaying measurements must be improved.
Begin with a definition of information-it must be understood. Most
process control professionals state that information conveyed to opera-
tors should be limited to that requiring action within a relatively short
time period, typically a shift. Most also agree that conveying long-term
threats and too much description to operators, for example, outer race
bearing failure probable within a week or month, is irrelevant, distract-
ing, and potentially counterproductive. A case can be made that differen-
tiation between specific failure types is relevant to an operator only if it
affects action required. Too much long-term information may create an
indifference that ultimately results in missing a real requirement for
immediate action.
Information must be displayed in a clear, understandable fashion. Indi-
vidual measurements, such as vibration expressed in engineering units,
and even measurement-versus-time trends do not meet requirements if
too much skilled interpretation is required. Expert decision advisory sys-
tems will occupy a vastly expanded and important function in the data-
to-information-conversion process. Expressing complex data as a single
measure of machine life remaining, or as a normalized condition index
has been ~uggested.~ Information displayed in a friendly form such as a
smiling face has far greater value and impact than values and even
trends. Not surprisingly, there is a scientific basis for smiling faces and
other imagery used to translate complex multidimensional measurements
into an easily interpretable form.8

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