Efficient Plant October 2017 - 14
feature | reliability & profitability
and area asset sets of the operation.
Accurate Reliability Curves are Key
After real-time reliability risk
is measured, real-time reliability
control becomes possible (See
Fig. 2). This significantly and
positively extends traditional
maintenance management. For
example, if it is likely that a compressor will fail within the next
six hours, i.e., the risk is high, the
real-time reliability controller, in
the form of the process operator
Fig. 1: Accurate reliability curves, coupled with condition and
process measurement, make it possible to precisely measure
(this function could eventually
be handled by an automatic asset
controller), might immediately respond by slowing compressor
rotation, thus extending the reliability time
is the Driver
threshold and avoiding a short-term failure.
This provides time to optimally and more permanently respond to the condition.
The availability of real-time reliability control
will lead to a two-level asset-reliability model
for industrial operations (See Fig. 3). At the
lowest level will be real-time control offering
real-time reliability risk measurement and the
appropriate control response to increase asset
Fig. 2: After real-time reliability risk is
measured, real-time reliability control
reliability. At the upper level will be sophisticatbecomes possible. This significantly
ed asset-reliability-management functions, such
and positively extends traditional
as prognostics and maintenance planning and
scheduling. Together, this two-tier approach
In a Two-Level
Fig. 3: Real-time reliability control
leads to a two-level asset-reliability
model for industrial operations.
Leads to Empowerment
Fig. 4: Real-time accounting enables profitability
measurement, leading to an empowered workforce,
through specialized asset analytics software, to
control the real-time operation profitability.
will increase asset reliability, which naturally
leads to more output from every asset in the
operation and increased operational reliability.
However, the two-tier approach does not offer
a direct tie to improving safe operational
profitability, which is the ultimate objective. It
is tempting to assume that any increase in asset
reliability directly translates into profitability
improvement, but this might not be the case.
For instance, if the compressor in the above
example is slowed down to extend its time to
failure, the short-term result will be a less profitability because throughput will also be reduced.
Therefore, the best way to ensure that this
new approach has a positive impact is to directly
measure operational profitability factors in real
time, at the asset level. In fact, as with a reliability-control loop, an operational profitability control loop can be developed once the profitability
factors are measured (See Fig. 3).
Using real-time accounting can enable
profitability measurement, which would then
empower the workforce, through specialized
asset analytics software, to control the real-time
operation profitability. Figure 4 illustrates a
functional, not necessarily physical, model. The
line from Operational Profitability Measurement to Operational Profitability Control can
only be deployed when automatic reliability
Reliability Drives Profitability
Fig. 5: Profitability control cascades to reliability
control, enabling implementation in a manner
that drives optimal profitability. Operational
profitability controller output serves as the set
point for the reliability controller.