Transcript MaintenanceManagement

Maintenance management
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Maintenance Management Loop
Study preparation
RAMS requirements
Failure modes and
effect analysis
Maintenance types
and intervals
Grouping of
maintenance activities
Overall operation,
mainteance and repair
Data Analysis and
improvement analysis
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Database
Report
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Acutal maintenance
and inspection
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Maintenance and
inspection plan
FMEA/FMECA
 Failure Mode, (Criticality) and Effects Analysis
 A Failure Mode and Effects Analysis is often the first step
in a systems reliability study
 It involves reviewing as many components, assemblies
and subsystems as possible to identify possible failure
modes and the causes and effects of such failures
 For each component, the failure modes and their resulting
effects on the rest of the system are written onto a specific
FMCEA form
 FMECA is an important element of RCM
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Maintenance and inspection types and
intervals
 The main objective of this step is to determine the type
and frequencies of maintenance and inspection tasks
 In principle each failure mode/failure cause in the FMECA
should be combated by a maintenance task
 The RCM logic of an RCM analysis will be a starting point
for identifying relevant maintenance tasks
 To determine optimal frequencies of maintenance tasks it
is usually required to establish a cost model to optimize
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Grouping of maintenance and inspection
work
 When the maintenance tasks are identified, and
frequencies set it will usually be natural to group these
activities into maintenance packages, each package
describing what to do, and when to do it
 It is a challenge to establish such an optimal grouping
strategy
 Why grouping
 Save “set-up” cost
 Convenience
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Maintenance and inspection plan
 A maintenance program shall be established, which
includes written procedures for maintaining, testing, and
repairing the various components
 Such a program is often implemented by a computerized
maintenance management system (CMMS)
 A main task of the CMMS is to manage all work orders for
preventive maintenance
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Failures need corrective maintenance
 Failures represent technical component failures (e.g. rail
breakage, defect breaks etc), and deviations (e.g.
geometrical deviations of the track)
 Failures and deviations require repair, overhaul etc
 Typically a work order for corrective maintenance (CM) is
issued
 The CMMS will also manage these work orders
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Reporting of result from maintenance and
inspection
 All maintenance work (functional testing, preventive
maintenance, and corrective maintenance) shall be
reported into an electronic maintenance database
 The information to report depends on the type of
maintenance work
 Important information to report
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Exact description of failed/maintained unit
Failure mode (CM)
Component state (PM)
Failure cause (CM)
Effect of failure (CM)
Direct cost of maintenance action
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Database
 The database used in the maintenance management loop
is a conceptual term
 A RAMS database may be realized as a part of the CMMS
 It is essential that the database system contains
necessary information for a proper data analysis
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Data analysis and improvement analysis
 A proper failure cause analysis (FCA), or root cause
analysis (RCA)
 Investigation into the failure reports to identify common
cause problems (CCF)
 Updated reliability data that was used in quantitative risk
analyses/maintenance optimization models
 Verification of assumption related to safety critical
functions/safety barriers
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Restrictions
 When maintenance comes out of control (large backlog) it
is important to initiate operational restrictions
 Closing a railway line
 Reducing speed
 Stop production
 Use of compensating measures
 Restrictions will also be necessary when the system
integrity is threatened by weather conditions such as rain,
frost, snow, high temperature etc.
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Exercise
 What is meant by “the maintenance management loop is
NOT closed”
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