PDM Program Class Acceptance
Predictive Maintenance (PDM) has become widely accepted
in the Global Marine Industry by the Classification Societies.
Requirements for mandatory open-and-inspect maintenance
during a standard 5-year survey cycle are no longer
required if a PDM program exists.
ABS Program Overview
ABS states in their 1995 Guideline, “Consideration will
be given to extending overhauls (opening out) beyond
the 5-year cycle where Planned Maintenance and Condition
Monitoring programs are in effect”. This program has led
the way for substantial savings for owners over the past
15 years. PDM has virtually eliminated time-based
maintenance with the use of condition-based analysis
and proactive actions.
Why switch to a PDM Program?
Under the normal class required time-based interval
maintenance, maintenance actions were reactive, time
consuming and costly.
In some cases, the machinery failed before scheduled
maintenance; other times required class inspections were
scheduled on equipment that did not need repairs costing
both substantial time and money.
The result was the useful life of the machine’s components
were lost and often the rebuild induced immediate failures
at re-start which negated the positive effects of the entire
Continuous Survey process.
Program Condition Monitoring Methods|
The frequency of acquiring Condition data is the basis
for a successful PDM Program. IMPACT Engineering supports
two levels of monitoring as follows:
Plan 1 – Highest Level of Monitoring (Q)
Shipboard Engineers acquire vibration and ultrasound
data using condition monitoring equipment on a Quarterly
(Q) basis or as needed. Classification Societies require
that a certified external specialist (e.g., IMPACT Engineering)
collect the readings on an Annual basis and prepare a
detailed diagnostic report of the findings and
recommendations on a Semi-Annual basis. This benefit
allows for maximum onboard diagnostics.
Plan 2 – Moderate Level of Monitoring (SA)
Semi-Annual (SA) vibration and ultrasound monitoring
is performed by an engineer from IMPACT Engineering
dockside or during a 2-3 day voyage. Again IMPACT
Engineering provides a detailed diagnostic report of the
findings and recommendations after each survey. This
level of monitoring does not require the substantial
training or equipment costs in Plan 1. Semi-Annual
monitoring has proven to be extremely effective in
detecting typical machinery faults and cost effective to
implement and support world-wide.
Substantial maintenance savings are attainable in the
Marine Industry due to deferred maintenance, increased
machinery reliability, and substantially reduced unscheduled
downtime when a PDM program is implemented. Due to
fierce competition, no Marine Operator should be without
a Predictive Maintenance strategy.