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1. Information gathering and project familiarisation • (to be validated with project team)
• Equipment List
• Analysis of Process Flow Diagrams (PFDs) and Piping and 4. Model construction and simulation
• build RAM Model using Bureau Veritas Monte Carlo
Instrumentation Diagrams (P&IDs)
• understanding of failure modes Simulator Optimise©
• historical and estimated failure rates • perform simulation with various model inputs
• logistic times (understanding of crew staffing, spare parts
5. Results generating
holding etc.) • quantify performance of the system in terms of overall
• failure impact on production, capacity and safety
• understanding of any third party requests for shutdown availability
• presentation of p10, p50 and p90 probabilities of
2. Development of Reliability Data Set
• historical operating records exceedance for understanding confidence levels
• Offshore Reliability Data (Oreda) • annual availability distribution
• equipment vendors • average duration spent delivering different capacities
• engineering judgment • system criticalities
• (to be validated with project team) • high equipment contributors to downtime

3. Assumptions 6. Recommendations
• identification of equipment critical to production • understanding of bottlenecks, and changes in equipment
• development of Reliability Block Diagrams (RBDs)
configuration
(understanding of equipment redundancy and • understanding of spare holding and lead times to source
configuration)
• operations and maintenance spares optimised against availability targets and the total
• identification of sensitivity analyses costs of holding spares
• maintainability and operability sensitivity cases

Table 1 - RAM Analysis flaring etc.); The latest addition to the suite, Optimise V3©, is
Process • LNG storage. combining the:
• detailed RAM capabilities of traditional RAM
Transfer of the stored LNG is via side by side
offloading to LNGCs. software, including planned and unplanned
Availability target of the full supply chain (i.e. from downtime, operations and maintenance
subsea to LNG carriers) has been set at 90%. philosophies, production and demand
profiles;
Objectives of the RAM analysis • shipping simulation capabilities of sophisticated
‘tank to tank’ shipping tools, including fleet
Main purpose of the RAM analysis was to: configuration, weather and mechanical delays,
• evaluate the availability of the FLNG tidal and night berthing restrictions, and a
host of other aspects necessary for realistic
development in terms of LNG loaded; shipping simulation;
• identify and rank the critical systems and • detailed modeling of receiving terminal
operations, including storage and send out.
components contributing to production
losses; Optimise V3© also allows multiple loading ports
• provide a baseline set of results for use in and multiple receiving ports to be simulated in a
further sensitivity analysis; single model.
• identify reliability issues in the designs to
recommend changes. Bureau Veritas RAM methodology

The following will present the detailed assumptions As presented in table 1, RAM analysis has been
to be taken into account when a RAM analysis is developed following a structured methodology
carried out for a FLNG development. based on 6 main steps:
• information gathering and project
Optimise©, Bureau Veritas RAM
software familiarization;
• development of reliability set of data;
Bureau Veritas uses its proprietary software suite • assumptions development and validation;
Optimise© to undertake RAM and supply chain • model construction and simulation through
analysis. Optimise© Monte Carlo Simulator software
has been used by Bureau Veritas extensively for the Bureau Veritas RAM software Optimise©;
the last 15 years and has been benchmarked • result generation;
against other similar software packages and actual • recommendations and sensitivity cases.
facility performance. Optimise© is compliant with
ISO 20815 production performance analysis Each step of the RAM analysis process will be now
requirements. detailed focusing on the specific approach required
for FLNG developments.

94 Impiantistica Italiana - Maggio-Giugno 2015