INTELLIGENT DIAGNOSTICS DELIVER BOTTOM-LINE BENEFITS
In this article, we explain the
technology employed by intelligent valve control and monitoring
equipment, and provide examples of
typical diagnostic features specific
to discrete installations. The article
also discusses how diagnostics are
useful in meeting predictive and
reliability maintenance improvement objectives.
During the last decade, production plants adopted preventive
maintenance strategies in an effort
to reduce their operating expenses,
improve reliability and increase on-stream performance. In order to
more effectively and intelligently
manage the risks of equipment failure, many plants have migrated
from a preventive maintenance
schedule to a Predictive Maintenance (PdM) regimen or incorporated PdM as a component of a Relia-bility-Centered Maintenance (RCM)
initiative (as defined by the technical standard SAE JA1011).
Today, end users are looking for
ways to determine which valves
actually require service, and more
importantly, which do not. At a minimum, even without interrogating
any performance data, the user can
identify how many successful cycles
were achieved prior to having a failure. Simply retrieving the cycles
and setting an alarm can be helpful
in scheduling shutdowns for maintenance and repairs.
Modern diagnostics provide
users with full visibility of valve and
actuator performance behaviors.
This enables prediction of normal
wear-and-tear within the automated
package, and also provides early
warnings should an anomaly occur.
ADVANCED CONTROLLERS HAVE
REVOLUTIONIZED AUTOMATED VALVE
PACKAGES BY OFFERING GREATER
INTELLIGENCE AND DIAGNOSTIC DATA
THAN CONVENTIONAL METHODS.
BY JACK DIFRANCO
For example, if an element of the automated valve package has a marginal component, the performance data would depict any deviation in the performance curve.
Despite advancements in process control technology and new strategies for asset
management, automation end users continue searching for better solutions addressing valve performance issues on the plant floor. From mechanical wear to electronic
malfunction, devices such as valves, actuators, solenoids, positioners, control monitors and transmitters all have some calculated failure mode.
MTBF and PFD reports by companies such as Exida can help end users determine
the level of probability of failure and safety integrity level of their entire control loop,
including the final control element—the automated valve. However, third-party companies that evaluate components of a device cannot be held responsible for selecting