Page 614 - Marine Structural Design

590 Part V Risk Assessment

Maintenance (RCM). The basic concept, principles and applications of PRA and RCM are
introduced for the development of an effective preventive maintenance program for offshore
facilities. PRA and RCM are methods that have been used for the development and
optimization of maintenance strategies in a structured and systematic way. They have been
widely used in the past years in many industries like nuclear power plants, aircraft's, and the
offshore industry.
34.1.2 Application

This chapter-is conceived to be a guide for the development and optimization of maintenance
strategies. The roles of PRA and RCM in the maintenance process are illustrated in Figure
34.1 (Rausand and Vatn, 1997). As shown in the figure, PRA analyses shall be performed for
screening and rating maintainable items.
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Total amount of maintainable items

Maintenance planning by RCM "Conventional" maintenance planning
method

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Maintenance planning I scheduling

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downtime, costs, etc.)
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I Reliability analysis (failure mode,
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y---____-----__
MTBF, MTTR, etc.) -I
Figure 34.1 The Roles of PRA and RCM in Maintenance Processes
The RCM analysis is then carried out on the items where preventive maintenance is
recommended. This means that RCM process should focus on maintenance-significant-items
(MSI), while the remaining items can be assigned with maintenance tasks by the more
traditional methods. However, all planned maintenance tasks will ultimately be integrated in a
common maintenance planning and control system.