Operating Context – The current condition, environment, and culture
in which an asset is operated in.
PF Curve – The degradation curve that shows a failure manifesting, the
equipment deteriorates to the point at which it can possibly be
detected (P). If the failure is not detected and mitigated, it continues
until a "hard" failure occurs (F).
PF Interval – is the window of opportunity during which an inspection
can possibly detect the imminent failure and address it. P-F intervals
can be measured in any unit associated with the exposure to the stress
(running time, cycles, miles, etc.).
Potential Failure – Is an identifiable condition that indicates a
functional failure is imminent.
Predictive Maintenance (PdM) – The use of measured physical
parameters against known acceptable limits for detecting, analyzing,
and identifying equipment problems before a failure occurs.
Preventive Maintenance (PM) – Maintenance carried out at
predetermined intervals, or to other prescribed criteria, and intended
to reduce the likelihood of a functional failure.
Reactive Maintenance – Maintenance repair work done as an
intermediate response to failure events, normally without planning,
always unscheduled.
Refurbishment – Extensive work intended to restore a plant of facility
to acceptable operating conditions.
Reliability (R) – The probability that an asset or item will perform its
intended functions for a specific period of time under stated
conditions. It is usually expressed as a percentage and measured by
the mean time between failures (MTBF).
Reliability Availability Maintainability Safety (RAMS) – A model that
assesses a production system’s capabilities, whether it is in operation
or still in the design phase. The results from a RAM modeling will
identify possible causes of production losses and can examine possible
system alternatives.
Reliability Block Diagram (RBD) – Is a diagrammatic method for
showing how component reliability contributes to the success or
failure of a complex system.
Reliability Centered Maintenance (RCM) – A systematic and
structured process to develop an efficient and effective maintenance
plan for an asset to minimize the probability of failures. The process
insures safety and mission compliance.
Run to Failure (RTF) – A failure management policy that allows the
asset to be run to the failed state without effort to predict or prevent
this before it occurs.
Scheduled Discard Tasks – Replacement of an item at a fixed,
predetermined interval, regardless of its current condition.
Scheduled Restoration Tasks – A repair or restoration of an asset at a
predetermined interval, regardless of its current condition.
Uptime – Uptime is the time during which an asset or system is either
fully operational or is ready to perform its intended function. It is the
opposite of downtime.
Weibull Analysis – A statistical analysis used for life data analysis,
among other applications, consisting of plotting operating time at
failure versus percentage of accumulated failures on log-scale paper.
